import java.util.*;
import java.util.zip.*;
import java.util.List;
import java.util.regex.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;
import java.util.concurrent.locks.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.table.*;
import java.io.*;
import java.net.*;
import java.lang.reflect.*;
import java.lang.ref.*;
import java.lang.management.*;
import java.security.*;
import java.security.spec.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.imageio.*;
import java.math.*;
/*******************************************************************************
 * Copyright (c) 2010-2019 Haifeng Li
 *
 * Smile is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * Smile is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Smile.  If not, see <https://www.gnu.org/licenses/>.
 *******************************************************************************/

/**
 * The Edit distance between two strings is a metric for measuring the amount
 * of difference between two sequences. The Levenshtein distance between two
 * strings is given by the minimum number of operations needed to transform one
 * string into the other, where an operation is an insertion, deletion, or
 * substitution of a single character. A generalization of the Levenshtein
 * distance (Damerau-Levenshtein distance) allows the transposition of two
 * characters as an operation.
 * <p>
 * Given two strings x and y of length m and n (suppose n &ge; m), this
 * implementation takes O(ne) time and O(mn) space by an extended Ukkonen's
 * algorithm in case of unit cost, where e is the edit distance between x and y.
 * Thus this algorithm is output sensitive. The smaller the distance, the faster
 * it runs.
 * <p>
 * For weighted cost, this implements the regular dynamic programming algorithm,
 * which takes O(mn) time and O(m) space.
 *
 * @author Haifeng Li
 */
class main {

final static class EditDistance /*implements Metric<String>*/ {
  /**
   * Weight matrix for weighted Levenshtein distance.
   */
  private IIntArray2D weight;

  /**
   * Radius of Sakoe-Chiba band
   */
  private double r = -1;

  /**
   * Calculate Damerau or basic Levenshitein distance.
   */
  private boolean damerau = false;

  /**
   * Cost matrix. Because Java automatically initialize arrays, it
   * takes O(mn) to declare this cost matrix every time before
   * calculate edit distance. But the whole point of Berghel & Roach
   * algorithm is to calculate fewer cells than O(mn). Therefore,
   * we create this cost matrix here. Therefore, the methods using
   * this cost matrix is not multi-thread safe.
   */
  private IIntArray2D FKP;

  /**
   * The lambda to calculate FKP array.
   */
  private BRF brf;


  /**
   * Constructor. Multi-thread safe Levenshtein distance.
   */
  public EditDistance() {
      this(false);
  }

  /**
   * Constructor. Multi-thread safe Damerau-Levenshtein distance.
   * @param damerau if true, calculate Damerau-Levenshtein distance
   *                instead of plain Levenshtein distance.
   */
  public EditDistance(boolean damerau) {
      this.damerau = damerau;
  }

  /**
   * Constructor. Highly efficient Levenshtein distance but not multi-thread safe.
   * @param maxStringLength the maximum length of strings that will be
   * feed to this algorithm.
   */
  public EditDistance(int maxStringLength) {
      this(maxStringLength, false);
  }

  /**
   * Constructor. Highly efficient Damerau-Levenshtein distance but not multi-thread safe.
   * @param maxStringLength the maximum length of strings that will be
   *                        feed to this algorithm.
   * @param damerau if true, calculate Damerau-Levenshtein distance
   *                instead of plain Levenshtein distance.
   */
  public EditDistance(int maxStringLength, boolean damerau) {
      this.damerau = damerau;
      FKP = new IntArray2D(2*maxStringLength+1, maxStringLength+2);
      brf = damerau ? new DamerauBRF() : new LevenshteinBRF();
  }

  /**
   * Constructor. Weighted Levenshtein distance without path
   * constraints. Only insertion, deletion, and substitution operations are
   * supported.
   */
  public EditDistance(int[][] weight) {
      this(weight, -1);
  }

  /**
   * Constructor. Weighted Levenshtein distance with
   * Sakoe-Chiba band, which improve computational cost. Only
   * insertion, deletion, and substitution operations are supported.
   * @param radius the window width of Sakoe-Chiba band in terms of percentage of sequence length.
   */
  public EditDistance(int[][] weight, double radius) {
      this.weight = new IntArray2D(weight);
      this.r = radius;
  }

  @Override
  public String toString() {
      if (damerau) {
          if (weight != null)
              return String.format("Damerau-Levenshtein Distance(radius = %d, weight = %s)", r, weight.toString());
          else
              return "Damerau-Levenshtein Distance";
      } else {
          if (weight != null)
              return String.format("Levenshtein Distance(radius = %d, weight = %s)", r, weight.toString());
          else
              return  "Levenshtein Distance";
      }
  }

  /**
   * Edit distance between two strings. O(mn) time and O(n) space for weighted
   * edit distance. O(ne) time and O(mn) space for unit cost edit distance.
   * For weighted edit distance, this method is multi-thread safe. However,
   * it is NOT multi-thread safe for unit cost edit distance.
   */
  public double d(String x, String y) {
      if (weight != null)
          return weightedEdit(x, y);
      else if (FKP == null || x.length() == 1 || y.length() == 1)
          return damerau ? damerau(x, y) : levenshtein(x, y);
      else
          return br(x, y);
  }

  /**
   * Edit distance between two strings. O(mn) time and O(n) space for weighted
   * edit distance. O(ne) time and O(mn) space for unit cost edit distance.
   * For weighted edit distance, this method is multi-thread safe. However,
   * it is NOT multi-thread safe for unit cost edit distance.
   */
  public double d(char[] x, char[] y) {
      if (weight != null)
          return weightedEdit(x, y);
      else if (FKP == null || x.length == 1 || y.length == 1)
          return damerau ? damerau(x, y) : levenshtein(x, y);
      else
          return br(x, y);
  }

  /**
   * Weighted edit distance.
   */
  private double weightedEdit(char[] x, char[] y) {
      // switch parameters to use the shorter one as y to save space.
      if (x.length < y.length) {
          char[] swap = x;
          x = y;
          y = swap;
      }

      int radius = (int) Math.round(r * Math.max(x.length, y.length));

      double[][] d = new double[2][y.length + 1];

      d[0][0] = 0.0;
      for (int j = 1; j <= y.length; j++) {
          d[0][j] = d[0][j - 1] + weight.get(0, y[j]);
      }

      for (int i = 1; i <= x.length; i++) {
          d[1][0] = d[0][0] + weight.get(x[i], 0);

          int start = 1;
          int end = y.length;

          if (radius > 0) {
              start = i - radius;
              if (start > 1)
                  d[1][start - 1] = Double.POSITIVE_INFINITY;
              else
                  start = 1;

              end = i + radius;
              if (end < y.length)
                  d[1][end+1] = Double.POSITIVE_INFINITY;
              else
                  end = y.length;
          }

          for (int j = start; j <= end; j++) {
              double cost = weight.get(x[i - 1], y[j - 1]);
              d[1][j] = min3(
                      d[0][j] + weight.get(x[i - 1], 0), // deletion
                      d[1][j - 1] + weight.get(0, y[j - 1]), // insertion
                      d[0][j - 1] + cost); // substitution
          }

          double[] swap = d[0];
          d[0] = d[1];
          d[1] = swap;
      }

      return d[0][y.length];
  }

  /**
   * Weighted edit distance.
   */
  private double weightedEdit(String x, String y) {
      // switch parameters to use the shorter one as y to save space.
      if (x.length() < y.length()) {
          String swap = x;
          x = y;
          y = swap;
      }

      int radius = (int) Math.round(r * Math.max(x.length(), y.length()));

      double[][] d = new double[2][y.length() + 1];

      d[0][0] = 0.0;
      for (int j = 1; j <= y.length(); j++) {
          d[0][j] = d[0][j - 1] + weight.get(0, y.charAt(j));
      }

      for (int i = 1; i <= x.length(); i++) {
          d[1][0] = d[0][0] + weight.get(x.charAt(i), 0);

          int start = 1;
          int end = y.length();

          if (radius > 0) {
              start = i - radius;
              if (start > 1)
                  d[1][start - 1] = Double.POSITIVE_INFINITY;
              else
                  start = 1;

              end = i + radius;
              if (end < y.length())
                  d[1][end+1] = Double.POSITIVE_INFINITY;
              else
                  end = y.length();
          }

          for (int j = start; j <= end; j++) {
              double cost = weight.get(x.charAt(i - 1), y.charAt(j - 1));
              d[1][j] = min3(
                      d[0][j] + weight.get(x.charAt(i - 1), 0), // deletion
                      d[1][j - 1] + weight.get(0, y.charAt(j - 1)), // insertion
                      d[0][j - 1] + cost); // substitution
          }

          double[] swap = d[0];
          d[0] = d[1];
          d[1] = swap;
      }

      return d[0][y.length()];
  }

  /**
   * Berghel & Roach's extended Ukkonen's algorithm.
   */
  private int br(char[] x, char[] y) {
      if (x.length > y.length) {
          char[] swap = x;
          x = y;
          y = swap;
      }

      final int m = x.length;
      final int n = y.length;

      int ZERO_K = n;

      if (n+2 > FKP.ncols())
          FKP = new IntArray2D(2*n+1, n+2);

      for (int k = -ZERO_K; k < 0; k++) {
          int p = -k - 1;
          FKP.set(k + ZERO_K, p + 1, Math.abs(k) - 1);
          FKP.set(k + ZERO_K, p, Integer.MIN_VALUE);
      }

      FKP.set(ZERO_K, 0, -1);

      for (int k = 1; k <= ZERO_K; k++) {
          int p = k - 1;
          FKP.set(k + ZERO_K, p + 1, -1);
          FKP.set(k + ZERO_K, p, Integer.MIN_VALUE);
      }

      int p = n - m - 1;

      do {
          p++;

          for (int i = (p - (n-m))/2; i >= 1; i--) {
              brf.f(x, y, FKP, ZERO_K, n-m+i, p-i);
          }

          for (int i = (n-m+p)/2; i >= 1; i--) {
              brf.f(x, y, FKP, ZERO_K, n-m-i, p-i);
          }

          brf.f(x, y, FKP, ZERO_K, n - m, p);
      } while (FKP.get((n - m) + ZERO_K, p) != m);

      return p - 1;
  }

  /**
   * Berghel & Roach's extended Ukkonen's algorithm.
   */
  private int br(String x, String y) {
      if (x.length() > y.length()) {
          String swap = x;
          x = y;
          y = swap;
      }

      final int m = x.length();
      final int n = y.length();

      int ZERO_K = n;

      if (n+3 > FKP.ncols())
          FKP = new IntArray2D(2*n+1, n+3);

      for (int k = -ZERO_K; k < 0; k++) {
          int p = -k - 1;
          FKP.set(k + ZERO_K, p + 1, Math.abs(k) - 1);
          FKP.set(k + ZERO_K, p, Integer.MIN_VALUE);
      }

      FKP.set(ZERO_K, 0, -1);

      for (int k = 1; k <= ZERO_K; k++) {
          int p = k - 1;
          FKP.set(k + ZERO_K, p + 1, -1);
          FKP.set(k + ZERO_K, p, Integer.MIN_VALUE);
      }

      int p = n - m - 1;

      do {
          p++;

          for (int i = (p - (n-m))/2; i >= 1; i--) {
              brf.f(x, y, FKP, ZERO_K, n-m+i, p-i);
          }

          for (int i = (n-m+p)/2; i >= 1; i--) {
              brf.f(x, y, FKP, ZERO_K, n-m-i, p-i);
          }

          brf.f(x, y, FKP, ZERO_K, n - m, p);
      } while (FKP.get((n - m) + ZERO_K, p) != m);

      return p - 1;
  }

  private static class LevenshteinBRF implements BRF {
      @Override
      public void f(char[] x, char[] y, IIntArray2D FKP, int ZERO_K, int k, int p) {
          int t = max3(FKP.get(k + ZERO_K, p) + 1, FKP.get(k - 1 + ZERO_K, p), FKP.get(k + 1 + ZERO_K, p) + 1);
          int mnk = Math.min(x.length, y.length - k);

          while (t < mnk && x[t] == y[t + k]) {
              t++;
          }

          FKP.set(k + ZERO_K, p + 1, t);
      }

      @Override
      public void f(String x, String y, IIntArray2D FKP, int ZERO_K, int k, int p) {
          int t = max3(FKP.get(k + ZERO_K, p) + 1, FKP.get(k - 1 + ZERO_K, p), FKP.get(k + 1 + ZERO_K, p) + 1);
          int mnk = Math.min(x.length(), y.length() - k);

          while (t < mnk && x.charAt(t) == y.charAt(t + k)) {
              t++;
          }

          FKP.set(k + ZERO_K, p + 1, t);
      }
  }

  /**
   * Calculate FKP arrays in BR's algorithm with support of transposition operation.
   */
  private static class DamerauBRF implements BRF {
      @Override
      public void f(char[] x, char[] y, IIntArray2D FKP, int ZERO_K, int k, int p) {
          int t = FKP.get(k + ZERO_K, p) + 1;
          int mnk = Math.min(x.length, y.length - k);

          if (t >= 1 && k + t >= 1 && t < mnk) {
              if (x[t - 1] == y[k + t] && x[t] == y[k + t - 1]) {
                  t++;
              }
          }

          t = max3(FKP.get(k - 1 + ZERO_K, p), FKP.get(k + 1 + ZERO_K, p) + 1, t);

          while (t < mnk && x[t] == y[t + k]) {
              t++;
          }

          FKP.set(k + ZERO_K, p + 1, t);
      }

      @Override
      public void f(String x, String y, IIntArray2D FKP, int ZERO_K, int k, int p) {
          int t = FKP.get(k + ZERO_K, p) + 1;
          int mnk = Math.min(x.length(), y.length() - k);

          if (t >= 1 && k + t >= 1 && t < mnk) {
              if (x.charAt(t - 1) == y.charAt(k + t) && x.charAt(t) == y.charAt(k + t - 1)) {
                  t++;
              }
          }

          t = max3(FKP.get(k - 1 + ZERO_K, p), FKP.get(k + 1 + ZERO_K, p) + 1, t);

          while (t < mnk && x.charAt(t) == y.charAt(t + k)) {
              t++;
          }

          FKP.set(k + ZERO_K, p + 1, t);
      }
  }
  
  static interface BRF {
      /**
       * Calculate FKP arrays in BR's algorithm.
       */
      void f(char[] x, char[] y, IIntArray2D FKP, int ZERO_K, int k, int p);
      /**
       * Calculate FKP arrays in BR's algorithm.
       */
      void f(String x, String y, IIntArray2D FKP, int ZERO_K, int k, int p);
  }

    /**
     * Levenshtein distance between two strings allows insertion, deletion,
     * or substitution of characters. O(mn) time and O(n) space.
     * Multi-thread safe.
     */
    public static int levenshtein(String x, String y) {
        // switch parameters to use the shorter one as y to save space.
        if (x.length() < y.length()) {
            String swap = x;
            x = y;
            y = swap;
        }

        int[][] d = new int[2][y.length() + 1];

        for (int j = 0; j <= y.length(); j++) {
            d[0][j] = j;
        }

        for (int i = 1; i <= x.length(); i++) {
            d[1][0] = i;

            for (int j = 1; j <= y.length(); j++) {
                int cost = x.charAt(i - 1) == y.charAt(j - 1) ? 0 : 1;
                d[1][j] = min3(
                        d[0][j] + 1, // deletion
                        d[1][j - 1] + 1, // insertion
                        d[0][j - 1] + cost); // substitution
            }
            int[] swap = d[0];
            d[0] = d[1];
            d[1] = swap;
        }

        return d[0][y.length()];
    }

    /**
     * Levenshtein distance between two strings allows insertion, deletion,
     * or substitution of characters. O(mn) time and O(n) space.
     * Multi-thread safe.
     */
    public static int levenshtein(char[] x, char[] y) {
        // switch parameters to use the shorter one as y to save space.
        if (x.length < y.length) {
            char[] swap = x;
            x = y;
            y = swap;
        }

        int[][] d = new int[2][y.length + 1];

        for (int j = 0; j <= y.length; j++) {
            d[0][j] = j;
        }

        for (int i = 1; i <= x.length; i++) {
            d[1][0] = i;

            for (int j = 1; j <= y.length; j++) {
                int cost = x[i - 1] == y[j - 1] ? 0 : 1;
                d[1][j] = min3(
                        d[0][j] + 1, // deletion
                        d[1][j - 1] + 1, // insertion
                        d[0][j - 1] + cost); // substitution
            }
            int[] swap = d[0];
            d[0] = d[1];
            d[1] = swap;
        }

        return d[0][y.length];
    }

    /**
     * Damerau-Levenshtein distance between two strings allows insertion,
     * deletion, substitution, or transposition of characters.
     * O(mn) time and O(n) space. Multi-thread safe.
     */
    public static int damerau(String x, String y) {
        // switch parameters to use the shorter one as y to save space.
        if (x.length() < y.length()) {
            String swap = x;
            x = y;
            y = swap;
        }

        int[][] d = new int[3][y.length() + 1];

        for (int j = 0; j <= y.length(); j++) {
            d[1][j] = j;
        }

        for (int i = 1; i <= x.length(); i++) {
            d[2][0] = i;

            for (int j = 1; j <= y.length(); j++) {
                int cost = x.charAt(i-1) == y.charAt(j-1) ? 0 : 1;
                d[2][j] = min3(
                        d[1][j] + 1,       // deletion
                        d[2][j-1] + 1,       // insertion
                        d[1][j-1] + cost); // substitution

                if (i > 1 && j > 1) {
                    if (x.charAt(i-1) == y.charAt(j-2) && x.charAt(i-2) == y.charAt(j-1))
                        d[2][j] = Math.min(d[2][j], d[0][j-2] + cost);   // damerau
                }
            }

            int[] swap = d[0];
            d[0] = d[1];
            d[1] = d[2];
            d[2] = swap;
        }

        return d[1][y.length()];
    }

    /**
     * Damerau-Levenshtein distance between two strings allows insertion,
     * deletion, substitution, or transposition of characters.
     * O(mn) time and O(n) space. Multi-thread safe.
     */
    public static int damerau(char[] x, char[] y) {
        // switch parameters to use the shorter one as y to save space.
        if (x.length < y.length) {
            char[] swap = x;
            x = y;
            y = swap;
        }

        int[][] d = new int[3][y.length + 1];

        for (int j = 0; j <= y.length; j++) {
            d[1][j] = j;
        }

        for (int i = 1; i <= x.length; i++) {
            d[2][0] = i;

            for (int j = 1; j <= y.length; j++) {
                int cost = x[i-1] == y[j-1] ? 0 : 1;
                d[2][j] = min3(
                        d[1][j] + 1,       // deletion
                        d[2][j-1] + 1,       // insertion
                        d[1][j-1] + cost); // substitution

                if (i > 1 && j > 1) {
                    if (x[i-1] == y[j-2] && x[i-2] == y[j-1])
                        d[2][j] = Math.min(d[2][j], d[0][j-2] + cost);   // damerau
                }
            }

            int[] swap = d[0];
            d[0] = d[1];
            d[1] = d[2];
            d[2] = swap;
        }

        return d[1][y.length];
    }
}
static int min3(int a, int b, int c) {
  return min(min(a, b), c);
}

static double min3(double a, double b, double c) {
  return min(min(a, b), c);
}
static int max3(int a, int b, int c) {
  return max(max(a, b), c);
}

static double max3(double a, double b, double c) {
  return max(max(a, b), c);
}


static int min(int a, int b) {
  return Math.min(a, b);
}

static long min(long a, long b) {
  return Math.min(a, b);
}

static float min(float a, float b) { return Math.min(a, b); }
static float min(float a, float b, float c) { return min(min(a, b), c); }

static double min(double a, double b) {
  return Math.min(a, b);
}

static double min(double[] c) {
  double x = Double.MAX_VALUE;
  for (double d : c) x = Math.min(x, d);
  return x;
}

static float min(float[] c) {
  float x = Float.MAX_VALUE;
  for (float d : c) x = Math.min(x, d);
  return x;
}

static byte min(byte[] c) {
  byte x = 127;
  for (byte d : c) if (d < x) x = d;
  return x;
}

static short min(short[] c) {
  short x = 0x7FFF;
  for (short d : c) if (d < x) x = d;
  return x;
}

static int min(int[] c) {
  int x = Integer.MAX_VALUE;
  for (int d : c) if (d < x) x = d;
  return x;
}
static int max(int a, int b) { return Math.max(a, b); }
static int max(int a, int b, int c) { return max(max(a, b), c); }
static long max(int a, long b) { return Math.max((long) a, b); }
static long max(long a, long b) { return Math.max(a, b); }
static double max(int a, double b) { return Math.max((double) a, b); }
static float max(float a, float b) { return Math.max(a, b); }
static double max(double a, double b) { return Math.max(a, b); }

static int max(Collection<Integer> c) {
  int x = Integer.MIN_VALUE;
  for (int i : c) x = max(x, i);
  return x;
}

static double max(double[] c) {
  if (c.length == 0) return Double.MIN_VALUE;
  double x = c[0];
  for (int i = 1; i < c.length; i++) x = Math.max(x, c[i]);
  return x;
}

static float max(float[] c) {
  if (c.length == 0) return Float.MAX_VALUE;
  float x = c[0];
  for (int i = 1; i < c.length; i++) x = Math.max(x, c[i]);
  return x;
}

static byte max(byte[] c) {
  byte x = -128;
  for (byte d : c) if (d > x) x = d;
  return x;
}

static short max(short[] c) {
  short x = -0x8000;
  for (short d : c) if (d > x) x = d;
  return x;
}

static int max(int[] c) {
  int x = Integer.MIN_VALUE;
  for (int d : c) if (d > x) x = d;
  return x;
}


static interface IIntArray2D {
  public int nrows();
  public int ncols();

  /** Returns A(i, j). */
  public int get(int i, int j);

  /** Sets A(i, j). */
  public int set(int i, int j, int x);
}/*******************************************************************************
 * Copyright (c) 2010-2019 Haifeng Li
 *
 * Smile is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * Smile is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Smile.  If not, see <https://www.gnu.org/licenses/>.
 *******************************************************************************/

static class IntArray2D implements IIntArray2D {
  private int[] A;
  private int nrows;
  private int ncols;

  public IntArray2D(int[][] A) {
      this.nrows = A.length;
      this.ncols = A[0].length;
      this.A = new int[nrows*ncols];

      int pos = 0;
      for (int i = 0; i < nrows; i++) {
          System.arraycopy(A[i], 0, this.A, pos, ncols);
          pos += ncols;
      }
  }

  /**
   * Constructor of all-zero matrix.
   */
  public IntArray2D(int rows, int cols) {
      this.nrows = rows;
      this.ncols = cols;
      A = new int[rows*cols];
  }

  /**
   * Constructor. Fill the matrix with given value.
   */
  public IntArray2D(int rows, int cols, int value) {
      this(rows, cols);
      if (value != 0.0)
          Arrays.fill(A, value);
  }

  /**
   * Constructor.
   * @param value the array of matrix values arranged in row major format
   */
  public IntArray2D(int rows, int cols, int[] value) {
      this.nrows = rows;
      this.ncols = cols;
      this.A = value;
  }

  public int nrows() {
      return nrows;
  }

  public int ncols() {
      return ncols;
  }

  /** Returns A(i, j). Useful in Scala. */
  public int apply(int i, int j) {
      return A[i*ncols + j];
  }

  /** Returns A(i, j). */
  public int get(int i, int j) {
      return A[i*ncols + j];
  }

  /** Sets A(i, j). */
  public int set(int i, int j, int x) {
      return A[i*ncols + j] = x;
  }

  public int add(int i, int j, int x) {
      return A[i*ncols + j] += x;
  }

  public int sub(int i, int j, int x) {
      return A[i*ncols + j] -= x;
  }

  public int mul(int i, int j, int x) {
      return A[i*ncols + j] *= x;
  }

  public int div(int i, int j, int x) {
      return A[i*ncols + j] /= x;
  }

  public IntArray2D add(IntArray2D b) {
      if (nrows() != b.nrows() || ncols() != b.ncols()) {
          throw new IllegalArgumentException("Matrix is not of same size.");
      }

      for (int i = 0; i < A.length; i++) {
          A[i] += b.A[i];
      }
      return this;
  }

  public IntArray2D sub(IntArray2D b) {
      if (nrows() != b.nrows() || ncols() != b.ncols()) {
          throw new IllegalArgumentException("Matrix is not of same size.");
      }

      for (int i = 0; i < A.length; i++) {
          A[i] -= b.A[i];
      }
      return this;
  }

  public IntArray2D mul(IntArray2D b) {
      if (nrows() != b.nrows() || ncols() != b.ncols()) {
          throw new IllegalArgumentException("Matrix is not of same size.");
      }

      for (int i = 0; i < A.length; i++) {
          A[i] *= b.A[i];
      }
      return this;
  }

  public IntArray2D div(IntArray2D b) {
      if (nrows() != b.nrows() || ncols() != b.ncols()) {
          throw new IllegalArgumentException("Matrix is not of same size.");
      }

      for (int i = 0; i < A.length; i++) {
          A[i] /= b.A[i];
      }
      return this;
  }

  public IntArray2D add(int x) {
      for (int i = 0; i < A.length; i++) {
          A[i] += x;
      }

      return this;
  }

  public IntArray2D sub(int x) {
      for (int i = 0; i < A.length; i++) {
          A[i] -= x;
      }

      return this;
  }

  public IntArray2D mul(int x) {
      for (int i = 0; i < A.length; i++) {
          A[i] *= x;
      }

      return this;
  }

  public IntArray2D div(int x) {
      for (int i = 0; i < A.length; i++) {
          A[i] /= x;
      }

      return this;
  }

  public long sum() {
      long s = 0;
      for (int i = 0; i < A.length; i++) {
          s += A[i];
      }

      return s;
  }

  @Override
  public String toString() {
      return toString(false);
  }

  /**
   * Returns the string representation of matrix.
   * @param full Print the full matrix if true. Otherwise,
   *             print only top left 7 x 7 submatrix.
   */
  public String toString(boolean full) {
      return full ? toString(nrows(), ncols()) : toString(7, 7);
  }

  /**
   * Returns the string representation of matrix.
   * @param m the number of rows to print.
   * @param n the number of columns to print.
   */
  public String toString(int m, int n) {
      StringBuilder sb = new StringBuilder();
      m = Math.min(m, nrows());
      n = Math.min(n, ncols());

      String newline = n < ncols() ? "...\n" : "\n";

      for (int i = 0; i < m; i++) {
          for (int j = 0; j < n; j++) {
              sb.append(String.format("%d  ", get(i, j)));
          }
          sb.append(newline);
      }

      if (m < nrows()) {
          sb.append("  ...\n");
      }

      return sb.toString();
  }
}

static void add(BitSet bs, int i) {
  bs.set(i);
}

static <A> boolean add(Collection<A> c, A a) {
  return c != null && c.add(a);
}


static void add(Container c, Component x) {
  addToContainer(c, x);
}

static BigInteger mul(BigInteger a, BigInteger b) {
  return a.multiply(b);
}

static BigInteger mul(BigInteger a, long b) {
  return a.multiply(bigint(b));
}
static String div(Object contents, Object... params) {
  return hfulltag("div", contents, params);
}

static BigInteger div(BigInteger a, BigInteger b) {
  return a.divide(b);
}

static BigInteger div(BigInteger a, int b) {
  return a.divide(bigint(b));
}
// get purpose 1: access a list/array/map (safer version of x.get(y))

static <A> A get(List<A> l, int idx) {
  return l != null && idx >= 0 && idx < l(l) ? l.get(idx) : null;
}

// seems to conflict with other signatures
/*static <A, B> B get(Map<A, B> map, A key) {
  ret map != null ? map.get(key) : null;
}*/

static <A> A get(A[] l, int idx) {
  return idx >= 0 && idx < l(l) ? l[idx] : null;
}

// default to false
static boolean get(boolean[] l, int idx) {
  return idx >= 0 && idx < l(l) ? l[idx] : false;
}

// get purpose 2: access a field by reflection or a map

static Object get(Object o, String field) {
  try {
    if (o == null) return null;
    if (o instanceof Class) return get((Class) o, field);
    
    if (o instanceof Map)
      return ((Map) o).get(field);
      
    Field f = getOpt_findField(o.getClass(), field);
    if (f != null) {
      makeAccessible(f);
      return f.get(o);
    }
      
    
  } catch (Exception e) {
    throw asRuntimeException(e);
  }
  throw new RuntimeException("Field '" + field + "' not found in " + o.getClass().getName());
}

static Object get_raw(String field, Object o) {
  return get_raw(o, field);
}

static Object get_raw(Object o, String field) { try {
  if (o == null) return null;
  Field f = get_findField(o.getClass(), field);
  makeAccessible(f);
  return f.get(o);
} catch (Exception __e) { throw rethrow(__e); } }

static Object get(Class c, String field) {
  try {
    Field f = get_findStaticField(c, field);
    makeAccessible(f);
    return f.get(null);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Field get_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
}

static Field get_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
}

static Object get(String field, Object o) {
  return get(o, field);
}


static void addToContainer(final Container a, final Component b) {
  if (a != null && b != null) { swing(new Runnable() {  public void run() { try {  a.add(b); 
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "a.add(b);"; }}); }
}
static BigInteger bigint(String s) {
  return new BigInteger(s);
}

static BigInteger bigint(long l) {
  return BigInteger.valueOf(l);
}
static String hfulltag(String tag) {
  return hfulltag(tag, "");
}

static String hfulltag(String tag, Object contents, Object... params) {
  return hopeningTag(tag, params) + str(contents) + "</" + tag + ">";
}
static int l(Object[] a) { return a == null ? 0 : a.length; }
static int l(boolean[] a) { return a == null ? 0 : a.length; }
static int l(byte[] a) { return a == null ? 0 : a.length; }
static int l(short[] a) { return a == null ? 0 : a.length; }
static int l(long[] a) { return a == null ? 0 : a.length; }
static int l(int[] a) { return a == null ? 0 : a.length; }
static int l(float[] a) { return a == null ? 0 : a.length; }
static int l(double[] a) { return a == null ? 0 : a.length; }
static int l(char[] a) { return a == null ? 0 : a.length; }
static int l(Collection c) { return c == null ? 0 : c.size(); }
static int l(Iterator i) { return iteratorCount_int_close(i); } // consumes the iterator && closes it if possible
static int l(Map m) { return m == null ? 0 : m.size(); }
static int l(CharSequence s) { return s == null ? 0 : s.length(); }
static long l(File f) { return f == null ? 0 : f.length(); }



static int l(Object o) {
  return o == null ? 0
    : o instanceof String ? l((String) o)
    : o instanceof Map ? l((Map) o)
    : o instanceof Collection ? l((Collection) o)
    : o instanceof Object[] ? l((Object[]) o)
    : o instanceof boolean[] ? l((boolean[]) o)
    : o instanceof byte[] ? l((byte[]) o)
    : o instanceof char[] ? l((char[]) o)
    : o instanceof short[] ? l((short[]) o)
    : o instanceof int[] ? l((int[]) o)
    : o instanceof float[] ? l((float[]) o)
    : o instanceof double[] ? l((double[]) o)
    : o instanceof long[] ? l((long[]) o)
    : (Integer) call(o, "size");
}









static Field getOpt_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}
static Field makeAccessible(Field f) {
  try {
    f.setAccessible(true);
  } catch (Throwable e) {
    // Note: The error reporting only works with Java VM option --illegal-access=deny
    vmBus_send("makeAccessible_error",e, f);
  }
  return f;
}

static Method makeAccessible(Method m) {
  try {
    m.setAccessible(true);
  } catch (Throwable e) {
    vmBus_send("makeAccessible_error",e, m);
  }
  return m;
}

static Constructor makeAccessible(Constructor c) {
  try {
    c.setAccessible(true);
  } catch (Throwable e) {
    vmBus_send("makeAccessible_error",e, c);
  }
  return c;
}
static RuntimeException asRuntimeException(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  return t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}
static RuntimeException rethrow(Throwable t) {
  
  if (t instanceof Error)
    _handleError((Error) t);
  
  throw t instanceof RuntimeException ? (RuntimeException) t : new RuntimeException(t);
}

static RuntimeException rethrow(String msg, Throwable t) {
  throw new RuntimeException(msg, t);
}


static Object swing(Object f) {
  return swingAndWait(f);
}

static <A> A swing(F0<A> f) {
  return (A) swingAndWait(f);
}

static <A> A swing(IF0<A> f) {
  return (A) swingAndWait(f);
}
static String hopeningTag(String tag, Map params) {
  return hopeningTag(tag, mapToParams(params));
}

static String hopeningTag(String tag, Object... params) {
  StringBuilder buf = new StringBuilder();
  buf.append("<" + tag);
  for (int i = 0; i < l(params); i += 2) {
    String name = (String) get(params, i);
    Object val = get(params, i+1);
    if (nempty(name) && val != null) {
      if (val == html_valueLessParam())
        buf.append(" " + name);
      else {
        String s = str(val);
        if (!empty(s))
          buf.append(" " + name + "=" + htmlQuote(s));
      }
    }
  }
  buf.append(">");
  return str(buf);
}
static String str(Object o) {
  return o == null ? "null" : o.toString();
}

static String str(char[] c) {
  return new String(c);
}
static <A> int iteratorCount_int_close(Iterator<A> i) { try {
  int n = 0;
  if (i != null) while (i.hasNext()) { i.next(); ++n; }
  if (i instanceof AutoCloseable) ((AutoCloseable) i).close();
  return n;
} catch (Exception __e) { throw rethrow(__e); } }
static Object call(Object o) {
  return callF(o);
}

// varargs assignment fixer for a single string array argument
static Object call(Object o, String method, String[] arg) {
  return call(o, method, new Object[] {arg});
}

static Object call(Object o, String method, Object... args) {
  //ret call_cached(o, method, args);
  return call_withVarargs(o, method, args);
}
static void vmBus_send(String msg, Object... args) {
  Object arg = vmBus_wrapArgs(args);
  pcallFAll(vm_busListeners_live(), msg, arg);
  pcallFAll(vm_busListenersByMessage_live().get(msg), msg, arg);
}

static void vmBus_send(String msg) {
  vmBus_send(msg, (Object) null);
}
static void _handleError(Error e) {
  call(javax(), "_handleError", e);
}


static void swingAndWait(Runnable r) { try {
  if (isAWTThread())
    r.run();
  else
    EventQueue.invokeAndWait(addThreadInfoToRunnable(r));
} catch (Exception __e) { throw rethrow(__e); } }

static Object swingAndWait(final Object f) {
  if (isAWTThread())
    return callF(f);
  else {
    final Var result = new Var();
    swingAndWait(new Runnable() {  public void run() { try { 
      result.set(callF(f));
    
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "result.set(callF(f));"; }});
    return result.get();
  }
}
static Object[] mapToParams(Map map) {
  return mapToObjectArray(map);
}
static boolean nempty(Collection c) {
  return !empty(c);
}

static boolean nempty(CharSequence s) {
  return !empty(s);
}

static boolean nempty(Object[] o) { return !empty(o); }
static boolean nempty(byte[] o) { return !empty(o); }
static boolean nempty(int[] o) { return !empty(o); }

static boolean nempty(Map m) {
  return !empty(m);
}

static boolean nempty(Iterator i) {
  return i != null && i.hasNext();
}

static boolean nempty(Object o) { return !empty(o); }
static Object html_valueLessParam_cache;
static Object html_valueLessParam() { if (html_valueLessParam_cache == null) html_valueLessParam_cache = html_valueLessParam_load(); return html_valueLessParam_cache; }

static Object html_valueLessParam_load() {
  return new Object();
}
static boolean empty(Collection c) { return c == null || c.isEmpty(); }
static boolean empty(CharSequence s) { return s == null || s.length() == 0; }
static boolean empty(Map map) { return map == null || map.isEmpty(); }
static boolean empty(Object[] o) { return o == null || o.length == 0; }
static boolean empty(Object o) {
  if (o instanceof Collection) return empty((Collection) o);
  if (o instanceof String) return empty((String) o);
  if (o instanceof Map) return empty((Map) o);
  if (o instanceof Object[]) return empty((Object[]) o);
  if (o instanceof byte[]) return empty((byte[]) o);
  if (o == null) return true;
  throw fail("unknown type for 'empty': " + getType(o));
}

static boolean empty(Iterator i) { return i == null || !i.hasNext(); }

static boolean empty(float[] a) { return a == null || a.length == 0; }
static boolean empty(int[] a) { return a == null || a.length == 0; }
static boolean empty(long[] a) { return a == null || a.length == 0; }
static boolean empty(byte[] a) { return a == null || a.length == 0; }
static boolean empty(short[] a) { return a == null || a.length == 0; }



static boolean empty(File f) { return getFileSize(f) == 0; }
static String htmlQuote(String s) {
  return "\"" + htmlencode_forParams(s) + "\"";
}
static Map<Class, ArrayList<Method>> callF_cache = newDangerousWeakHashMap();


  static <A> A callF(F0<A> f) {
    return f == null ? null : f.get();
  }





  static <A> A callF(IF0<A> f) {
    return f == null ? null : f.get();
  }









  static <A> void callF(VF1<A> f, A a) {
    if (f != null) f.get(a);
  }


static Object callF(Object f, Object... args) { try {
  if (f instanceof String)
    return callMC((String) f, args);
  if (f instanceof Runnable) {
    ((Runnable) f).run();
    return null;
  }
  if (f == null) return null;
  
  Class c = f.getClass();
  ArrayList<Method> methods;
  synchronized(callF_cache) {
    methods = callF_cache.get(c);
    if (methods == null)
      methods = callF_makeCache(c);
  }
  
  int n = l(methods);
  if (n == 0) {
    
    throw fail("No get method in " + getClassName(c));
  }
  if (n == 1) return invokeMethod(methods.get(0), f, args);
  for (int i = 0; i < n; i++) {
    Method m = methods.get(i);
    if (call_checkArgs(m, args, false))
      return invokeMethod(m, f, args);
  }
  throw fail("No matching get method in " + getClassName(c));
} catch (Exception __e) { throw rethrow(__e); } }

// used internally
static ArrayList<Method> callF_makeCache(Class c) {
  ArrayList<Method> l = new ArrayList();
  Class _c = c;
  do {
    for (Method m : _c.getDeclaredMethods())
      if (m.getName().equals("get")) {
        makeAccessible(m);
        l.add(m);
      }
    if (!l.isEmpty()) break;
    _c = _c.getSuperclass();
  } while (_c != null);
  callF_cache.put(c, l);
  return l;
}
static Object call_withVarargs(Object o, String method, Object... args) { try {
  if (o == null) return null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    Method me = cache.findStaticMethod(method, args);
    if (me != null)
      return invokeMethod(me, null, args);
      
    // try varargs
    List<Method> methods = cache.cache.get(method);
    if (methods != null) methodSearch: for (Method m : methods) {
      { if (!(m.isVarArgs())) continue; }
      { if (!(isStaticMethod(m))) continue; }
      Object[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        return invokeMethod(m, null, newArgs);
    }
    
    throw fail("Method " + c.getName() + "." + method + "(" + joinWithComma(classNames(args)) + ") not found");
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(method, args);
    if (me != null)
      return invokeMethod(me, o, args);
      
    // try varargs
    List<Method> methods = cache.cache.get(method);
    if (methods != null) methodSearch: for (Method m : methods) {
      { if (!(m.isVarArgs())) continue; }
      Object[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        return invokeMethod(m, o, newArgs);
    }
    
    throw fail("Method " + c.getName() + "." + method + "(" + joinWithComma(classNames(args)) + ") not found in " + c);
  }
} catch (Exception __e) { throw rethrow(__e); } }
static Object vmBus_wrapArgs(Object... args) {
  return empty(args) ? null
    : l(args) == 1 ? args[0]
    : args;
}
static void pcallFAll(Collection l, Object... args) {
  if (l != null) for (Object f : cloneList(l)) pcallF(f, args);
}

static void pcallFAll(Iterator it, Object... args) {
  while (it.hasNext()) pcallF(it.next(), args);
}
static Set vm_busListeners_live_cache;
static Set vm_busListeners_live() { if (vm_busListeners_live_cache == null) vm_busListeners_live_cache = vm_busListeners_live_load(); return vm_busListeners_live_cache; }

static Set vm_busListeners_live_load() {
  return vm_generalIdentityHashSet("busListeners");
}
static Map<String, Set> vm_busListenersByMessage_live_cache;
static Map<String, Set> vm_busListenersByMessage_live() { if (vm_busListenersByMessage_live_cache == null) vm_busListenersByMessage_live_cache = vm_busListenersByMessage_live_load(); return vm_busListenersByMessage_live_cache; }

static Map<String, Set> vm_busListenersByMessage_live_load() {
  return vm_generalHashMap("busListenersByMessage");
}
static Class javax() {
  return getJavaX();
}


// TODO: test if android complains about this
static boolean isAWTThread() {
  if (isAndroid()) return false;
  if (isHeadless()) return false;
  return isAWTThread_awt();
}

static boolean isAWTThread_awt() {
  return SwingUtilities.isEventDispatchThread();
}
static Runnable addThreadInfoToRunnable(final Object r) {
  final Object info = _threadInfo();
  return info == null ? asRunnable(r) : new Runnable() {  public void run() { try {  _inheritThreadInfo(info); callF(r); 
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "_inheritThreadInfo(info); callF(r);"; }};
}
static Object[] mapToObjectArray(Map map) {
  List l = new ArrayList();
  for (Object o : keys(map)) {
    l.add(o);
    l.add(map.get(o));
  }
  return toObjectArray(l);
}

static Object[] mapToObjectArray(Object f, Collection l) {
  int n = l(l);
  Object[] array = new Object[n];
  if (n != 0) {
    Iterator it = iterator(l);
    for (int i = 0; i < n; i++)
      array[i] = callF(f, it.next());
  }
  return array;
}

static Object[] mapToObjectArray(Object f, Object[] l) {
  int n = l(l);
  Object[] array = new Object[n];
  for (int i = 0; i < n; i++)
    array[i] = callF(f, l[i]);
  return array;
}
static RuntimeException fail() { throw new RuntimeException("fail"); }
static RuntimeException fail(Throwable e) { throw asRuntimeException(e); }
static RuntimeException fail(Object msg) { throw new RuntimeException(String.valueOf(msg)); }
static RuntimeException fail(String msg) { throw new RuntimeException(msg == null ? "" : msg); }
static RuntimeException fail(String msg, Throwable innerException) { throw new RuntimeException(msg, innerException); }

static String getType(Object o) {
  return getClassName(o);
}
static long getFileSize(String path) {
  return path == null ? 0 : new File(path).length();
}

static long getFileSize(File f) {
  return f == null ? 0 : f.length();
}
static String htmlencode_forParams(String s) {
  if (s == null) return "";
  StringBuilder out = new StringBuilder(Math.max(16, s.length()));
  for (int i = 0; i < s.length(); i++) {
      char c = s.charAt(i);
      /*if (c >= 0x100)
        out.append("&#x").append(charToHex(c)).append(';');
      else*/ if (c > 127 || c == '"' || c == '<' || c == '>') {
          out.append("&#");
          out.append((int) c);
          out.append(';');
      } else
          out.append(c);
  }
  return out.toString();
}
static <A, B> Map<A, B> newDangerousWeakHashMap() {
  return _registerDangerousWeakMap(synchroMap(new WeakHashMap()));
}

// initFunction: voidfunc(Map) - is called initially, and after clearing the map
static <A, B> Map<A, B> newDangerousWeakHashMap(Object initFunction) {
  return _registerDangerousWeakMap(synchroMap(new WeakHashMap()), initFunction);
}
static HashMap<String, List<Method>> callMC_cache = new HashMap();
static String callMC_key;
static Method callMC_value;

// varargs assignment fixer for a single string array argument
static Object callMC(String method, String[] arg) {
  return callMC(method, new Object[] {arg});
}

static Object callMC(String method, Object... args) { try {
  Method me;
  if (callMC_cache == null) callMC_cache = new HashMap(); // initializer time workaround
  synchronized(callMC_cache) {
    me = method == callMC_key ? callMC_value : null;
  }
  if (me != null) try {
    return invokeMethod(me, null, args);
  } catch (IllegalArgumentException e) {
    throw new RuntimeException("Can't call " + me + " with arguments " + classNames(args), e);
  }

  List<Method> m;
  synchronized(callMC_cache) {
    m = callMC_cache.get(method);
  }
  if (m == null) {
    if (callMC_cache.isEmpty()) {
      callMC_makeCache();
      m = callMC_cache.get(method);
    }
    if (m == null) throw fail("Method named " + method + " not found in main");
  }
  int n = m.size();
  if (n == 1) {
    me = m.get(0);
    synchronized(callMC_cache) {
      callMC_key = method;
      callMC_value = me;
    }
    try {
      return invokeMethod(me, null, args);
    } catch (IllegalArgumentException e) {
      throw new RuntimeException("Can't call " + me + " with arguments " + classNames(args), e);
    }
  }
  for (int i = 0; i < n; i++) {
    me = m.get(i);
    if (call_checkArgs(me, args, false))
      return invokeMethod(me, null, args);
  }
  throw fail("No method called " + method + " with arguments (" + joinWithComma(getClasses(args)) + ") found in main");
} catch (Exception __e) { throw rethrow(__e); } }

static void callMC_makeCache() {
  synchronized(callMC_cache) {
    callMC_cache.clear();
    Class _c = (Class) mc(), c = _c;
    while (c != null) {
      for (Method m : c.getDeclaredMethods())
        if ((m.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0) {
          makeAccessible(m);
          multiMapPut(callMC_cache, m.getName(), m);
        }
      c = c.getSuperclass();
    }
  }
}
static String getClassName(Object o) {
  return o == null ? "null" : o instanceof Class ? ((Class) o).getName() : o.getClass().getName();
}
static Object invokeMethod(Method m, Object o, Object... args) { try {
  try {
    return m.invoke(o, args);
  } catch (InvocationTargetException e) {
    throw rethrow(getExceptionCause(e));
  } catch (IllegalArgumentException e) {
    throw new IllegalArgumentException(e.getMessage() + " - was calling: " + m + ", args: " + joinWithSpace(classNames(args)));
  }
} catch (Exception __e) { throw rethrow(__e); } }
static boolean call_checkArgs(Method m, Object[] args, boolean debug) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != args.length) {
    if (debug)
      print("Bad parameter length: " + args.length + " vs " + types.length);
    return false;
  }
  for (int i = 0; i < types.length; i++) {
    Object arg = args[i];
    if (!(arg == null ? !types[i].isPrimitive()
      : isInstanceX(types[i], arg))) {
      if (debug)
        print("Bad parameter " + i + ": " + arg + " vs " + types[i]);
      return false;
    }
  }
  return true;
}
static final Map<Class, _MethodCache> callOpt_cache = newDangerousWeakHashMap();

static Object callOpt_cached(Object o, String methodName, Object... args) { try {
  if (o == null) return null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    // TODO: (super-rare) case where method exists static and non-static
    // with different args
    
    Method me = cache.findMethod(methodName, args);
    if (me == null || (me.getModifiers() & Modifier.STATIC) == 0) return null;
    return invokeMethod(me, null, args);
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(methodName, args);
    if (me == null) return null;
    return invokeMethod(me, o, args);
  }
} catch (Exception __e) { throw rethrow(__e); } }

static _MethodCache callOpt_getCache(Class c) {
  synchronized(callOpt_cache) {
    _MethodCache cache = callOpt_cache.get(c);
    if (cache == null)
      callOpt_cache.put(c, cache = new _MethodCache(c));
    return cache;
  }
}
static boolean isStaticMethod(Method m) {
  return methodIsStatic(m);
}
static Object[] massageArgsForVarArgsCall(Method m, Object[] args) {
  Class<?>[] types = m.getParameterTypes();
  int n = types.length-1, nArgs = args.length;
  if (nArgs < n) return null;
  for (int i = 0; i < n; i++)
    if (!argumentCompatibleWithType(args[i], types[i]))
      return null;
  Class varArgType = types[n].getComponentType();
  for (int i = n; i < nArgs; i++)
    if (!argumentCompatibleWithType(args[i], varArgType))
      return null;
  Object[] newArgs = new Object[n+1];
  arraycopy(args, 0, newArgs, 0, n);
  Object[] varArgs = arrayOfType(varArgType, nArgs-n);
  arraycopy(args, n, varArgs, 0, nArgs-n);
  newArgs[n] = varArgs;
  return newArgs;
}
static <A> String joinWithComma(Collection<A> c) {
  return join(", ", c);
}

static String joinWithComma(String... c) {
  return join(", ", c);
}


static String joinWithComma(Pair p) {
  return p == null ? "" : joinWithComma(str(p.a), str(p.b));
}

static List<String> classNames(Collection l) {
  return getClassNames(l);
}

static List<String> classNames(Object[] l) {
  return getClassNames(Arrays.asList(l));
}
static <A> ArrayList<A> cloneList(Iterable<A> l) {
  return l instanceof Collection ? cloneList((Collection) l) : asList(l);
}

static <A> ArrayList<A> cloneList(Collection<A> l) {
  if (l == null) return new ArrayList();
  synchronized(collectionMutex(l)) {
    return new ArrayList<A>(l);
  }
}
static Object pcallF(Object f, Object... args) {
  return pcallFunction(f, args);
}


static <A> A pcallF(F0<A> f) { try {
  return f == null ? null : f.get();
} catch (Throwable __e) { return null; } }





static <A> void pcallF(VF1<A> f, A a) {
  try {
    if (f != null) f.get(a);
  } catch (Throwable __e) { _handleException(__e); }
}

static Set vm_generalIdentityHashSet(Object name) {
  synchronized(get(javax(), "generalMap")) {
    Set set =  (Set) (vm_generalMap_get(name));
    if (set == null)
      vm_generalMap_put(name, set = syncIdentityHashSet());
    return set;
  }
}

static Map vm_generalHashMap(Object name) {
  synchronized(get(javax(), "generalMap")) {
    Map m =  (Map) (vm_generalMap_get(name));
    if (m == null)
      vm_generalMap_put(name, m = syncHashMap());
    return m;
  }
}

static Class __javax;

static Class getJavaX() { try {
  
  return __javax;
} catch (Exception __e) { throw rethrow(__e); } }


static int isAndroid_flag;

static boolean isAndroid() {
  if (isAndroid_flag == 0)
    isAndroid_flag = System.getProperty("java.vendor").toLowerCase().indexOf("android") >= 0 ? 1 : -1;
  return isAndroid_flag > 0;
}

static Boolean isHeadless_cache;

static boolean isHeadless() {
  if (isHeadless_cache != null) return isHeadless_cache;
  if (isAndroid()) return isHeadless_cache = true;
  if (GraphicsEnvironment.isHeadless()) return isHeadless_cache = true;
  
  // Also check if AWT actually works.
  // If DISPLAY variable is set but no X server up, this will notice.
  
  try {
    SwingUtilities.isEventDispatchThread();
    return isHeadless_cache = false;
  } catch (Throwable e) { return isHeadless_cache = true; }
}
static List<VF1<Map>> _threadInfo_makers = synchroList();

static Object _threadInfo() {
  if (empty(_threadInfo_makers)) return null;
  HashMap map = new HashMap();
  pcallFAll(_threadInfo_makers, map);
  return map;
}
static Runnable asRunnable(Object o) {
  return toRunnable(o);
}


static void _inheritThreadInfo(Object info) {
  _threadInheritInfo(info);
}
static <A, B> Set<A> keys(Map<A, B> map) {
  return map == null ? new HashSet() : map.keySet();
}

static Set keys(Object map) {
  return keys((Map) map);
}








static Object[] toObjectArray(Collection c) {
  List l = asList(c);
  return l.toArray(new Object[l.size()]);
}

static <A> Iterator<A> iterator(Iterable<A> c) {
  return c == null ? emptyIterator() : c.iterator();
}
static List<Pair> _registerDangerousWeakMap_preList;

static <A> A _registerDangerousWeakMap(A map) {
  return _registerDangerousWeakMap(map, null);
}

static <A> A _registerDangerousWeakMap(A map, Object init) {
  
  callF(init, map);
  
  if (init instanceof String) {
    final String f =  (String) init;
    init = new VF1<Map>() { public void get(Map map) { try {  callMC(f, map) ; } catch (Exception __e) { throw rethrow(__e); } }
  public String toString() { return "callMC(f, map)"; }};
  }
    
  if (javax() == null) {
    // We're in class init
    if (_registerDangerousWeakMap_preList == null) _registerDangerousWeakMap_preList = synchroList();
    _registerDangerousWeakMap_preList.add(pair(map, init));
    return map;
  }
  
  call(javax(), "_registerDangerousWeakMap", map, init);
  
  return map;
}

static void _onLoad_registerDangerousWeakMap() {
  
  assertNotNull(javax());
  if (_registerDangerousWeakMap_preList == null) return;
  for (Pair p : _registerDangerousWeakMap_preList)
    _registerDangerousWeakMap(p.a, p.b);
  _registerDangerousWeakMap_preList = null;
  
}
static Map synchroMap() {
  return synchroHashMap();
}

static <A, B> Map<A, B> synchroMap(Map<A, B> map) {
  return Collections.synchronizedMap(map);
}
static List<Class> getClasses(Object[] array) {
  List<Class> l = emptyList(l(array));
  for (Object o : array) l.add(_getClass(o));
  return l;
}
static Class mc() {
  return main.class;
}
static <A, B> void multiMapPut(Map<A, List<B>> map, A a, B b) {
  List<B> l = map.get(a);
  if (l == null)
    map.put(a, l = new ArrayList());
  l.add(b);
}


static Throwable getExceptionCause(Throwable e) {
  Throwable c = e.getCause();
  return c != null ? c : e;
}
static String joinWithSpace(Collection<String> c) {
  return join(" ", c);
}

static String joinWithSpace(String... c) {
  return join(" ", c);
}



static volatile StringBuffer local_log = new StringBuffer(); // not redirected


static volatile Appendable print_log = local_log; // might be redirected, e.g. to main bot

// in bytes - will cut to half that
static volatile int print_log_max = 1024*1024;
static volatile int local_log_max = 100*1024;

static boolean print_silent = false; // total mute if set

static Object print_byThread_lock = new Object();
static volatile ThreadLocal<Object> print_byThread; // special handling by thread - prefers F1<S, Bool>
static volatile Object print_allThreads;
static volatile Object print_preprocess;

static void print() {
  print("");
}

static <A> A print(String s, A o) {
  print((endsWithLetterOrDigit(s) ? s + ": " : s) + o);
  return o;
}

// slightly overblown signature to return original object...
static <A> A print(A o) {
  ping_okInCleanUp();
  if (print_silent) return o;
  String s = String.valueOf(o) + "\n";
  print_noNewLine(s);
  return o;
}

static void print_noNewLine(String s) {
  
  Object f = getThreadLocal(print_byThread_dontCreate());
  if (f == null) f = print_allThreads;
  if (f != null)
    // We do need the general callF machinery here as print_byThread is sometimes shared between modules
    if (isFalse(
      
      callF(f, s))) return;
  

  print_raw(s);
}

static void print_raw(String s) {
  
  if (print_preprocess != null) s = (String) callF(print_preprocess, s);
  s = fixNewLines(s);
  
  Appendable loc = local_log;
  Appendable buf = print_log;
  int loc_max = print_log_max;
  if (buf != loc && buf != null) {
    print_append(buf, s, print_log_max);
    loc_max = local_log_max;
  }
  if (loc != null) 
    print_append(loc, s, loc_max);
  System.out.print(s);
}

static void print_autoRotate() {
  
}
static boolean isInstanceX(Class type, Object arg) {
  if (type == boolean.class) return arg instanceof Boolean;
  if (type == int.class) return arg instanceof Integer;
  if (type == long.class) return arg instanceof Long;
  if (type == float.class) return arg instanceof Float;
  if (type == short.class) return arg instanceof Short;
  if (type == char.class) return arg instanceof Character;
  if (type == byte.class) return arg instanceof Byte;
  if (type == double.class) return arg instanceof Double;
  return type.isInstance(arg);
}
static boolean methodIsStatic(Method m) {
  return (m.getModifiers() & Modifier.STATIC) != 0;
}
static boolean argumentCompatibleWithType(Object arg, Class type) {
  return arg == null ? !type.isPrimitive() : isInstanceX(type, arg);
}
static void arraycopy(Object[] a, Object[] b) {
  if (a != null && b != null)
    arraycopy(a, 0, b, 0, min(a.length, b.length));
}

static void arraycopy(Object src, int srcPos, Object dest, int destPos, int n) {
  if (n != 0)
    System.arraycopy(src, srcPos, dest, destPos, n);
}
static <A> A[] arrayOfType(Class<A> type, int n) {
  return makeArray(type, n);
}

static <A> A[] arrayOfType(int n, Class<A> type) {
  return arrayOfType(type, n);
}
public static <A> String join(String glue, Iterable<A> strings) {
  if (strings == null) return "";
  if (strings instanceof Collection) {
    if (((Collection) strings).size() == 1) return str(first(((Collection) strings)));
  }
  StringBuilder buf = new StringBuilder();
  Iterator<A> i = strings.iterator();
  if (i.hasNext()) {
    buf.append(i.next());
    while (i.hasNext())
      buf.append(glue).append(i.next());
  }
  return buf.toString();
}

public static String join(String glue, String... strings) {
  return join(glue, Arrays.asList(strings));
}

static <A> String join(Iterable<A> strings) {
  return join("", strings);
}

static <A> String join(Iterable<A> strings, String glue) {
  return join(glue, strings);
}

public static String join(String[] strings) {
  return join("", strings);
}


static String join(String glue, Pair p) {
  return p == null ? "" : str(p.a) + glue + str(p.b);
}

static List<String> getClassNames(Collection l) {
  List<String> out = new ArrayList();
  if (l != null) for (Object o : l)
    out.add(o == null ? null : getClassName(o));
  return out;
}
static <A> ArrayList<A> asList(A[] a) {
  return a == null ? new ArrayList<A>() : new ArrayList<A>(Arrays.asList(a));
}

static ArrayList<Integer> asList(int[] a) {
  if (a == null) return null;
  ArrayList<Integer> l = emptyList(a.length);
  for (int i : a) l.add(i);
  return l;
}

static ArrayList<Float> asList(float[] a) {
  if (a == null) return null;
  ArrayList<Float> l = emptyList(a.length);
  for (float i : a) l.add(i);
  return l;
}
static <A> ArrayList<A> asList(Iterable<A> s) {
  if (s instanceof ArrayList) return (ArrayList) s;
  ArrayList l = new ArrayList();
  if (s != null)
    for (A a : s)
      l.add(a);
  return l;
}



static <A> ArrayList<A> asList(Enumeration<A> e) {
  ArrayList l = new ArrayList();
  if (e != null)
    while (e.hasMoreElements())
      l.add(e.nextElement());
  return l;
}
static Object collectionMutex(List l) {
  return l;
}

static Object collectionMutex(Object o) {
  if (o instanceof List) return o;
  
  String c = className(o);
  if (eq(c, "java.util.TreeMap$KeySet"))
    c = className(o = getOpt(o, "m"));
  else if (eq(c, "java.util.HashMap$KeySet"))
    c = className(o = get_raw(o, "this$0"));

  
  
  if (eqOneOf(c, "java.util.TreeMap$AscendingSubMap", "java.util.TreeMap$DescendingSubMap"))
    c = className(o = get_raw(o, "m"));
    
  
    
  return o;
}
static Object pcallFunction(Object f, Object... args) {
  try { return callFunction(f, args); } catch (Throwable __e) { _handleException(__e); }
  return null;
}
static volatile PersistableThrowable _handleException_lastException;
static List _handleException_onException = synchroList(ll("printStackTrace2"));

static void _handleException(Throwable e) {
  _handleException_lastException = persistableThrowable(e);
  
  Throwable e2 = innerException(e);
  if (e2.getClass() == RuntimeException.class && eq(e2.getMessage(), "Thread cancelled.") || e2 instanceof InterruptedException)
    return;
    
  for (Object f : cloneList(_handleException_onException)) try {
    callF(f, e);
  } catch (Throwable e3) {
    printStackTrace2(e3); // not using pcall here - it could lead to endless loops
  }
}

static Object vm_generalMap_get(Object key) {
  return vm_generalMap().get(key);
}
static Object vm_generalMap_put(Object key, Object value) {
  return mapPutOrRemove(vm_generalMap(), key, value);
}
static <A> Set<A> syncIdentityHashSet() {
  return (Set) synchronizedSet(identityHashSet());
}
static Map syncHashMap() {
  return synchroHashMap();
}


static Throwable printStackTrace2(Throwable e) {
  // we go to system.out now - system.err is nonsense
  print(getStackTrace2(e));
  return e;
}

static void printStackTrace2() {
  printStackTrace2(new Throwable());
}

static void printStackTrace2(String msg) {
  printStackTrace2(new Throwable(msg));
}

static <A> List<A> synchroList() {
  return Collections.synchronizedList(new ArrayList<A>());
}

static <A> List<A> synchroList(List<A> l) {
  return Collections.synchronizedList(l);
}

static Runnable toRunnable(final Object o) {
  if (o instanceof Runnable) return (Runnable) o;
  return new Runnable() {  public void run() { try {  callF(o) ;
} catch (Exception __e) { throw rethrow(__e); } }  public String toString() { return "callF(o)"; }};
}
static List<VF1<Map>> _threadInheritInfo_retrievers = synchroList();

static void _threadInheritInfo(Object info) {
  if (info == null) return;
  pcallFAll(_threadInheritInfo_retrievers, (Map) info);
}
static Iterator emptyIterator() {
  return Collections.emptyIterator();
}
static <A, B> Pair<A, B> pair(A a, B b) {
  return new Pair(a, b);
}

static <A> Pair<A, A> pair(A a) {
  return new Pair(a, a);
}
static <A> A assertNotNull(A a) {
  assertTrue(a != null);
  return a;
}

static <A> A assertNotNull(String msg, A a) {
  assertTrue(msg, a != null);
  return a;
}
static Map synchroHashMap() {
  return Collections.synchronizedMap(new HashMap());
}

static ArrayList emptyList() {
  return new ArrayList();
  //ret Collections.emptyList();
}

static ArrayList emptyList(int capacity) {
  return new ArrayList(max(0, capacity));
}

// Try to match capacity
static ArrayList emptyList(Iterable l) {
  return l instanceof Collection ? emptyList(((Collection) l).size()) : emptyList();
}

static ArrayList emptyList(Object[] l) {
  return emptyList(l(l));
}

// get correct type at once
static <A> ArrayList<A> emptyList(Class<A> c) {
  return new ArrayList();
}
static Class<?> _getClass(String name) {
  try {
    return Class.forName(name);
  } catch (ClassNotFoundException e) {
    return null; // could optimize this
  }
}

static Class _getClass(Object o) {
  return o == null ? null
    : o instanceof Class ? (Class) o : o.getClass();
}

static Class _getClass(Object realm, String name) {
  try {
    return getClass(realm).getClassLoader().loadClass(classNameToVM(name));
  } catch (ClassNotFoundException e) {
    return null; // could optimize this
  }
}
static boolean endsWithLetterOrDigit(String s) {
  return s != null && s.length() > 0 && Character.isLetterOrDigit(s.charAt(s.length()-1));
}
static void ping_okInCleanUp() {
  if (ping_pauseAll  || ping_anyActions )
    ping_impl(true);
}
// this syntax should be removed...
static Object getThreadLocal(Object o, String name) {
  ThreadLocal t =  (ThreadLocal) (getOpt(o, name));
  return t != null ? t.get() : null;
}

static <A> A getThreadLocal(ThreadLocal<A> tl) {
  return tl == null ? null : tl.get();
}

static <A> A getThreadLocal(ThreadLocal<A> tl, A defaultValue) {
  return or(getThreadLocal(tl), defaultValue);
}
static ThreadLocal<Object> print_byThread_dontCreate() {
  return print_byThread;
}
static boolean isFalse(Object o) {
  return eq(false, o);
}
static String fixNewLines(String s) {
  int i = indexOf(s, '\r');
  if (i < 0) return s;
  int l = s.length();
  StringBuilder out = new StringBuilder(l);
  out.append(s, 0, i);
  for (; i < l; i++) {
    char c = s.charAt(i);
    if (c != '\r')
      out.append(c);
    else {
      out.append('\n');
      if (i+1 < l && s.charAt(i+1) == '\n') ++i;
    }
  }
  return out.toString();
}
static void print_append(Appendable buf, String s, int max) { try {
  synchronized(buf) {
    buf.append(s);
    if (buf instanceof StringBuffer)
      rotateStringBuffer(((StringBuffer) buf), max);
    else if (buf instanceof StringBuilder)
      rotateStringBuilder(((StringBuilder) buf), max);
  }
} catch (Exception __e) { throw rethrow(__e); } }
static <A> A[] makeArray(Class<A> type, int n) {
  return (A[]) Array.newInstance(type, n);
}
static Object first(Object list) {
  return first((Iterable) list);
}

static <A> A first(List<A> list) {
  return empty(list) ? null : list.get(0);
}

static <A> A first(A[] bla) {
  return bla == null || bla.length == 0 ? null : bla[0];
}



static <A> A first(Iterator<A> i) {
  return i == null || !i.hasNext() ? null : i.next();
}

static <A> A first(Iterable<A> i) {
  if (i == null) return null;
  Iterator<A> it = i.iterator();
  return it.hasNext() ? it.next() : null;
}

static Character first(String s) { return empty(s) ? null : s.charAt(0); }


static <A, B> A first(Pair<A, B> p) {
  return p == null ? null : p.a;
}



static String className(Object o) {
  return getClassName(o);
}
static boolean eq(Object a, Object b) {
  return a == b || (a == null ? b == null : b != null && a.equals(b));
}


static Object getOpt(Object o, String field) {
  return getOpt_cached(o, field);
}

static Object getOpt(String field, Object o) {
  return getOpt_cached(o, field);
}

static Object getOpt_raw(Object o, String field) { try {
  Field f = getOpt_findField(o.getClass(), field);
  if (f == null) return null;
  makeAccessible(f);
  return f.get(o);
} catch (Exception __e) { throw rethrow(__e); } }

// access of static fields is not yet optimized
static Object getOpt(Class c, String field) { try {
  if (c == null) return null;
  Field f = getOpt_findStaticField(c, field);
  if (f == null) return null;
  makeAccessible(f);
  return f.get(null);
} catch (Exception __e) { throw rethrow(__e); } }

static Field getOpt_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}

static boolean eqOneOf(Object o, Object... l) {
  for (Object x : l) if (eq(o, x)) return true; return false;
}
static Object callFunction(Object f, Object... args) {
  return callF(f, args);
}
static <A> List<A> ll(A... a) {
  ArrayList l = new ArrayList(a.length);
  if (a != null) for (A x : a) l.add(x);
  return l;
}
static PersistableThrowable persistableThrowable(Throwable e) {
  return e == null ? null : new PersistableThrowable(e);
}
static Throwable innerException(Throwable e) {
  return getInnerException(e);
}
static Map vm_generalMap_map;

static Map vm_generalMap() {
  if (vm_generalMap_map == null)
    vm_generalMap_map = (Map) get(javax(), "generalMap");
  return vm_generalMap_map;
}
static <A, B> B mapPutOrRemove(Map<A, B> map, A key, B value) {
  if (map != null && key != null)
    if (value != null) return map.put(key, value);
    else return map.remove(key);
  return null;
}
static <A> Set<A> synchronizedSet() {
  return synchroHashSet();
}

static <A> Set<A> synchronizedSet(Set<A> set) {
  return Collections.synchronizedSet(set);
}
static <A> Set<A> identityHashSet() {
  return Collections.newSetFromMap(new IdentityHashMap());
}


static String getStackTrace2(Throwable e) {
  return hideCredentials(getStackTrace(unwrapTrivialExceptionWraps(e)) + replacePrefix("java.lang.RuntimeException: ", "FAIL: ",
    hideCredentials(str(innerException2(e)))) + "\n");
}
static void assertTrue(Object o) {
  if (!(eq(o, true) /*|| isTrue(pcallF(o))*/))
    throw fail(str(o));
}
  
static boolean assertTrue(String msg, boolean b) {
  if (!b)
    throw fail(msg);
  return b;
}

static boolean assertTrue(boolean b) {
  if (!b)
    throw fail("oops");
  return b;
}
static Class<?> getClass(String name) {
  try {
    return Class.forName(name);
  } catch (ClassNotFoundException e) {
    return null;
  }
}

static Class getClass(Object o) {
  return o instanceof Class ? (Class) o : o.getClass();
}

static Class getClass(Object realm, String name) { try {
  try {
    return getClass(realm).getClassLoader().loadClass(classNameToVM(name));
  } catch (ClassNotFoundException e) {
    return null;
  }
} catch (Exception __e) { throw rethrow(__e); } }
static String classNameToVM(String name) {
  return name.replace(".", "$");
}
//sbool ping_actions_shareable = true;
static volatile boolean ping_pauseAll = false;
static int ping_sleep = 100; // poll pauseAll flag every 100

static volatile boolean ping_anyActions = false;
static Map<Thread, Object> ping_actions = newWeakHashMap();
static ThreadLocal<Boolean> ping_isCleanUpThread = new ThreadLocal();


// always returns true
static boolean ping() {
  if (ping_pauseAll  || ping_anyActions ) ping_impl(true /* XXX */);
  //ifndef LeanMode ping_impl(); endifndef
  return true;
}

// returns true when it slept
static boolean ping_impl(boolean okInCleanUp) { try {
  if (ping_pauseAll && !isAWTThread()) {
    do
      Thread.sleep(ping_sleep);
    while (ping_pauseAll);
    return true;
  }
  
  
  if (ping_anyActions) { // don't allow sharing ping_actions
    if (!okInCleanUp && !isTrue(ping_isCleanUpThread.get()))
      failIfUnlicensed();
    Object action = null;
    synchronized(ping_actions) {
      if (!ping_actions.isEmpty()) {
        action = ping_actions.get(currentThread());
        if (action instanceof Runnable)
          ping_actions.remove(currentThread());
        if (ping_actions.isEmpty()) ping_anyActions = false;
      }
    }
    
    if (action instanceof Runnable)
      ((Runnable) action).run();
    else if (eq(action, "cancelled"))
      throw fail("Thread cancelled.");
  }
  
  
  return false;
} catch (Exception __e) { throw rethrow(__e); } }
static <A> A or(A a, A b) {
  return a != null ? a : b;
}
static <A> int indexOf(List<A> l, A a, int startIndex) {
  if (l == null) return -1;
  int n = l(l);
  for (int i = startIndex; i < n; i++)
    if (eq(l.get(i), a))
      return i;
  return -1;
}

static <A> int indexOf(List<A> l, int startIndex, A a) {
  return indexOf(l, a, startIndex);
}

static <A> int indexOf(List<A> l, A a) {
  if (l == null) return -1;
  return l.indexOf(a);
}

static int indexOf(String a, String b) {
  return a == null || b == null ? -1 : a.indexOf(b);
}

static int indexOf(String a, String b, int i) {
  return a == null || b == null ? -1 : a.indexOf(b, i);
}

static int indexOf(String a, char b) {
  return a == null ? -1 : a.indexOf(b);
}

static int indexOf(String a, int i, char b) {
  return indexOf(a, b, i);
}

static int indexOf(String a, char b, int i) {
  return a == null ? -1 : a.indexOf(b, i);
}

static int indexOf(String a, int i, String b) {
  return a == null || b == null ? -1 : a.indexOf(b, i);
}

static <A> int indexOf(A[] x, A a) {
  int n = l(x);
  for (int i = 0; i < n; i++)
    if (eq(x[i], a))
      return i;
  return -1;
}
static void rotateStringBuffer(StringBuffer buf, int max) { try {
  if (buf == null) return;
  synchronized(buf) {
    if (buf.length() <= max) return;
    
    try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
    buf.trimToSize();
  }
} catch (Exception __e) { throw rethrow(__e); } }
static void rotateStringBuilder(StringBuilder buf, int max) { try {
  if (buf == null) return;
  synchronized(buf) {
    if (buf.length() <= max) return;
    
    try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
    buf.trimToSize();
  }
} catch (Exception __e) { throw rethrow(__e); } }
//static final Map<Class, HashMap<S, Field>> getOpt_cache = newDangerousWeakHashMap(f getOpt_special_init);

static class getOpt_Map extends WeakHashMap {
  getOpt_Map() {
    if (getOpt_special == null) getOpt_special = new HashMap();
    clear();
  }
  
  public void clear() {
    super.clear();
    //print("getOpt clear");
    put(Class.class, getOpt_special);
    put(String.class, getOpt_special);
  }
}

static final Map<Class, HashMap<String, Field>> getOpt_cache = _registerDangerousWeakMap(synchroMap(new getOpt_Map()));
//static final Map<Class, HashMap<S, Field>> getOpt_cache = _registerWeakMap(synchroMap(new getOpt_Map));
static HashMap getOpt_special; // just a marker

/*static void getOpt_special_init(Map map) {
  map.put(Class.class, getOpt_special);
  map.put(S.class, getOpt_special);
}*/

static Object getOpt_cached(Object o, String field) { try {
  if (o == null) return null;

  Class c = o.getClass();
  HashMap<String, Field> map;
  synchronized(getOpt_cache) {
    map = getOpt_cache.get(c);
    if (map == null)
      map = getOpt_makeCache(c);
  }
  
  if (map == getOpt_special) {
    if (o instanceof Class)
      return getOpt((Class) o, field);
    /*if (o instanceof S)
      ret getOpt(getBot((S) o), field);*/
    if (o instanceof Map)
      return ((Map) o).get(field);
  }
    
  Field f = map.get(field);
  if (f != null) return f.get(o);
  
  return null;
} catch (Exception __e) { throw rethrow(__e); } }

// used internally - we are in synchronized block
static HashMap<String, Field> getOpt_makeCache(Class c) {
  HashMap<String, Field> map;
  if (isSubtypeOf(c, Map.class))
    map = getOpt_special;
  else {
    map = new HashMap();
    if (!reflection_classesNotToScan().contains(c.getName())) {
      Class _c = c;
      do {
        for (Field f : _c.getDeclaredFields()) {
          makeAccessible(f);
          String name = f.getName();
          if (!map.containsKey(name))
            map.put(name, f);
        }
        _c = _c.getSuperclass();
      } while (_c != null);
    }
  }
  if (getOpt_cache != null) getOpt_cache.put(c, map);
  return map;
}
static Throwable getInnerException(Throwable e) {
  if (e == null) return null;
  while (e.getCause() != null)
    e = e.getCause();
  return e;
}

static Throwable getInnerException(Runnable r) {
  return getInnerException(getException(r));
}
static <A> Set<A> synchroHashSet() {
  return Collections.synchronizedSet(new HashSet<A>());
}



static String hideCredentials(URL url) { return url == null ? null : hideCredentials(str(url)); }

static String hideCredentials(String url) {
  try {
    if (startsWithOneOf(url, "http://", "https://") && isAGIBlueDomain(hostNameFromURL(url))) return url;
  } catch (Throwable e) {
    print("HideCredentials", e);
  }
  return url.replaceAll("([&?])(_pass|key)=[^&\\s\"]*", "$1$2=<hidden>");
}

static String hideCredentials(Object o) {
  return hideCredentials(str(o));
}
static String getStackTrace(Throwable throwable) {
  lastException(throwable);
  return getStackTrace_noRecord(throwable);
}

static String getStackTrace_noRecord(Throwable throwable) {
  StringWriter writer = new StringWriter();
  throwable.printStackTrace(new PrintWriter(writer));
  return hideCredentials(writer.toString());
}

static String getStackTrace() {
  return getStackTrace_noRecord(new Throwable());
}
static Throwable unwrapTrivialExceptionWraps(Throwable e) {
  if (e == null) return e;
  while (e.getClass() == RuntimeException.class
    && e.getCause() != null && eq(e.getMessage(), str(e.getCause())))
    e = e.getCause();
  return e;
}
static String replacePrefix(String prefix, String replacement, String s) {
  if (!startsWith(s, prefix)) return s;
  return replacement + substring(s, l(prefix));
}
static Throwable innerException2(Throwable e) {
  if (e == null) return null;
  while (empty(e.getMessage()) && e.getCause() != null)
    e = e.getCause();
  return e;
}
static <A, B> Map<A, B> newWeakHashMap() {
  return _registerWeakMap(synchroMap(new WeakHashMap()));
}
static boolean isTrue(Object o) {
  if (o instanceof Boolean)
    return ((Boolean) o).booleanValue();
  if (o == null) return false;
  if (o instanceof ThreadLocal) // TODO: remove this
    return isTrue(((ThreadLocal) o).get());
  throw fail(getClassName(o));
}
static void failIfUnlicensed() {
  assertTrue("license off", licensed());
}
static Thread currentThread() {
  return Thread.currentThread();
}
static void clear(Collection c) {
  if (c != null) c.clear();
}
static <A, B> void put(Map<A, B> map, A a, B b) {
  if (map != null) map.put(a, b);
}

static <A> void put(List<A> l, int i, A a) {
  if (l != null && i >= 0 && i < l(l)) l.set(i, a);
}
static <A, B> B mapGet2(Map<A, B> map, A a) {
  return map == null ? null : map.get(a);
}

static <A, B> B mapGet2(A a, Map<A, B> map) {
  return map == null ? null : map.get(a);
}
static boolean isSubtypeOf(Class a, Class b) {
  return b.isAssignableFrom(a); // << always hated that method, let's replace it!
}
static Set<String> reflection_classesNotToScan_value = litset(
  "jdk.internal.loader.URLClassPath"
);

static Set<String> reflection_classesNotToScan() {
  return reflection_classesNotToScan_value;
}
static Throwable getException(Runnable r) {
  try {
    callF(r);
    return null;
  } catch (Throwable e) {
    return e;
  }
}


static boolean startsWithOneOf(String s, String... l) {
  for (String x : l) if (startsWith(s, x)) return true; return false;
}
static boolean isAGIBlueDomain(String domain) {
  return domainIsUnder(domain, theAGIBlueDomain());
}
static String hostNameFromURL(String url) { try {
  return new URL(url).getHost();
} catch (Exception __e) { throw rethrow(__e); } }
// PersistableThrowable doesn't hold GC-disturbing class references in backtrace
static volatile PersistableThrowable lastException_lastException;

static PersistableThrowable lastException() {
  return lastException_lastException;
}

static void lastException(Throwable e) {
  lastException_lastException = persistableThrowable(e);
}
static boolean startsWith(String a, String b) {
  return a != null && a.startsWith(b);
}

static boolean startsWith(String a, char c) {
  return nemptyString(a) && a.charAt(0) == c;
}



static boolean startsWith(List a, List b) {
  if (a == null || listL(b) > listL(a)) return false;
  for (int i = 0; i < listL(b); i++)
    if (neq(a.get(i), b.get(i)))
      return false;
  return true;
}


static String substring(String s, int x) {
  return substring(s, x, strL(s));
}

static String substring(String s, int x, int y) {
  if (s == null) return null;
  if (x < 0) x = 0;
  if (x >= s.length()) return "";
  if (y < x) y = x;
  if (y > s.length()) y = s.length();
  return s.substring(x, y);
}


static List _registerWeakMap_preList;

static <A> A _registerWeakMap(A map) {
  if (javax() == null) {
    // We're in class init
    if (_registerWeakMap_preList == null) _registerWeakMap_preList = synchroList();
    _registerWeakMap_preList.add(map);
    return map;
  }
  
  try {
    call(javax(), "_registerWeakMap", map);
  } catch (Throwable e) {
    printException(e);
    print("Upgrade JavaX!!");
  }
  return map;
}

static void _onLoad_registerWeakMap() {
  assertNotNull(javax());
  if (_registerWeakMap_preList == null) return;
  for (Object o : _registerWeakMap_preList)
    _registerWeakMap(o);
  _registerWeakMap_preList = null;
}
static volatile boolean licensed_yes = true;

static boolean licensed() {
  if (!licensed_yes) return false;
  ping_okInCleanUp();
  return true;
}

static void licensed_off() {
  licensed_yes = false;
}
static <A> HashSet<A> litset(A... items) {
  return lithashset(items);
}


static boolean domainIsUnder(String domain, String mainDomain) {
  return eqic(domain, mainDomain) || ewic(domain, "." + mainDomain);
}
static String theAGIBlueDomain() {
  return "agi.blue";
}
static boolean nemptyString(String s) {
  return s != null && s.length() > 0;
}
static int strL(String s) {
  return s == null ? 0 : s.length();
}
static int listL(Collection l) {
  return l == null ? 0 : l.size();
}
static boolean neq(Object a, Object b) {
  return !eq(a, b);
}
static <A extends Throwable> A printException(A e) {
  printStackTrace(e);
  return e;
}
static <A> HashSet<A> lithashset(A... items) {
  HashSet<A> set = new HashSet();
  for (A a : items) set.add(a);
  return set;
}


static boolean eqic(String a, String b) {
  
  
    if ((a == null) != (b == null)) return false;
    if (a == null) return true;
    return a.equalsIgnoreCase(b);
  
}



static boolean eqic(char a, char b) {
  if (a == b) return true;
  
    char u1 = Character.toUpperCase(a);
    char u2 = Character.toUpperCase(b);
    if (u1 == u2) return true;
  
  return Character.toLowerCase(u1) == Character.toLowerCase(u2);
}
static boolean ewic(String a, String b) {
  return endsWithIgnoreCase(a, b);
}


static <A extends Throwable> A printStackTrace(A e) {
  // we go to system.out now - system.err is nonsense
  print(getStackTrace(e));
  return e;
}

static void printStackTrace() {
  printStackTrace(new Throwable());
}

static void printStackTrace(String msg) {
  printStackTrace(new Throwable(msg));
}

static void printStackTrace(String msg, Throwable e) {
  printStackTrace(new Throwable(msg, e));
}


static String asString(Object o) {
  return o == null ? null : o.toString();
}
static boolean endsWithIgnoreCase(String a, String b) {
  int la = l(a), lb = l(b);
  return la >= lb && regionMatchesIC(a, la-lb, b, 0, lb);
}




static boolean regionMatchesIC(String a, int offsetA, String b, int offsetB, int len) {
  
  
    return a != null && a.regionMatches(true, offsetA, b, offsetB, len);
  
}


// immutable, has strong refs
final static class _MethodCache {
  final Class c;
  final HashMap<String, List<Method>> cache = new HashMap();
  
  _MethodCache(Class c) {
  this.c = c; _init(); }
  
  void _init() {
    Class _c = c;
    while (_c != null) {
      for (Method m : _c.getDeclaredMethods())
        if (!reflection_isForbiddenMethod(m))
          multiMapPut(cache, m.getName(), makeAccessible(m));
      _c = _c.getSuperclass();
    }
    
    // add default methods - this might lead to a duplication
    // because the overridden method is also added, but it's not
    // a problem except for minimal performance loss.
    for (Class intf : allInterfacesImplementedBy(c))
      for (Method m : intf.getDeclaredMethods())
        if (m.isDefault() && !reflection_isForbiddenMethod(m))
          multiMapPut(cache, m.getName(), makeAccessible(m));

    
  }
  
  // Returns only matching methods
  Method findMethod(String method, Object[] args) { try {
    List<Method> m = cache.get(method);
    
    if (m == null) return null;
    int n = m.size();
    for (int i = 0; i < n; i++) {
      Method me = m.get(i);
      if (call_checkArgs(me, args, false))
        return me;
    }
    return null;
  } catch (Exception __e) { throw rethrow(__e); } }
  
  Method findStaticMethod(String method, Object[] args) { try {
    List<Method> m = cache.get(method);
    if (m == null) return null;
    int n = m.size();
    for (int i = 0; i < n; i++) {
      Method me = m.get(i);
      if (isStaticMethod(me) && call_checkArgs(me, args, false))
        return me;
    }
    return null;
  } catch (Exception __e) { throw rethrow(__e); } }
}static abstract class VF1<A> implements IVF1<A> {
  public abstract void get(A a);
}static interface IF0<A> {
  A get();
}static class Var<A> implements IVar<A> {
  Var() {}
  Var(A v) {
  this.v = v;}

  
  A v; // you can access this directly if you use one thread
  
  public synchronized void set(A a) {
    if (v != a) {
      v = a;
      notifyAll();
    }
  }
  
  public synchronized A get() { return v; }
  public synchronized boolean has() { return v != null; }
  public synchronized void clear() { v = null; }
  
  public String toString() { return str(get()); }
}static class PersistableThrowable {
  String className;
  String msg;
  String stacktrace;
  
  PersistableThrowable() {}
  PersistableThrowable(Throwable e) {
    if (e == null)
      className = "Crazy Null Error";
    else {
      className = getClassName(e).replace('/', '.');
      msg = e.getMessage();
      stacktrace = getStackTrace_noRecord(e);
    }
  }
  
  public String toString() {
    return nempty(msg) ? className + ": " + msg : className;
  }
}static abstract class F0<A> {
  abstract A get();
}static class Pair<A, B> implements Comparable<Pair<A, B>> {
  A a;
  B b;

  Pair() {}
  Pair(A a, B b) {
  this.b = b;
  this.a = a;}
  
  public int hashCode() {
    return hashCodeFor(a) + 2*hashCodeFor(b);
  }
  
  public boolean equals(Object o) {
    if (o == this) return true;
    if (!(o instanceof Pair)) return false;
    Pair t = (Pair) o;
    return eq(a, t.a) && eq(b, t.b);
  }
  
  public String toString() {
    return "<" + a + ", " + b + ">";
  }
  
  public int compareTo(Pair<A, B> p) {
    if (p == null) return 1;
    int i = ((Comparable<A>) a).compareTo(p.a);
    if (i != 0) return i;
    return ((Comparable<B>) b).compareTo(p.b);
  }
}

static interface IVF1<A> {
  void get(A a);
}static interface IVar<A> {
  void set(A a);
  A get();
  default boolean has() { return get() != null; }
  default void clear() { set(null); }
}

static boolean reflection_isForbiddenMethod(Method m) {
  return m.getDeclaringClass() == Object.class
    && eqOneOf(m.getName(), "finalize", "clone", "registerNatives");
}
static Set<Class> allInterfacesImplementedBy(Class c) {
  if (c == null) return null;
  HashSet<Class> set = new HashSet();
  allInterfacesImplementedBy_find(c, set);
  return set;
}

static void allInterfacesImplementedBy_find(Class c, Set<Class> set) {
  if (c.isInterface() && !set.add(c)) return;
  do {
    for (Class intf : c.getInterfaces())
      allInterfacesImplementedBy_find(intf, set);
  } while ((c = c.getSuperclass()) != null);
}
static Method findMethod(Object o, String method, Object... args) {
  return findMethod_cached(o, method, args);
}

static boolean findMethod_checkArgs(Method m, Object[] args, boolean debug) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != args.length) {
    if (debug)
      System.out.println("Bad parameter length: " + args.length + " vs " + types.length);
    return false;
  }
  for (int i = 0; i < types.length; i++)
    if (!(args[i] == null || isInstanceX(types[i], args[i]))) {
      if (debug)
        System.out.println("Bad parameter " + i + ": " + args[i] + " vs " + types[i]);
      return false;
    }
  return true;
}
static Method findStaticMethod(Class c, String method, Object... args) {
  Class _c = c;
  while (c != null) {
    for (Method m : c.getDeclaredMethods()) {
      if (!m.getName().equals(method))
        continue;

      if ((m.getModifiers() & Modifier.STATIC) == 0 || !findStaticMethod_checkArgs(m, args))
        continue;

      return m;
    }
    c = c.getSuperclass();
  }
  return null;
}

static boolean findStaticMethod_checkArgs(Method m, Object[] args) {
  Class<?>[] types = m.getParameterTypes();
  if (types.length != args.length)
    return false;
  for (int i = 0; i < types.length; i++)
    if (!(args[i] == null || isInstanceX(types[i], args[i])))
      return false;
  return true;
}

static int hashCodeFor(Object a) {
  return a == null ? 0 : a.hashCode();
}
static <A> A set(A o, String field, Object value) {
  if (o == null) return null;
  if (o instanceof Class) set((Class) o, field, value);
  else try {
    Field f = set_findField(o.getClass(), field);
    makeAccessible(f);
    smartSet(f, o, value);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
  return o;
}

static void set(Class c, String field, Object value) {
  if (c == null) return;
  try {
    Field f = set_findStaticField(c, field);
    makeAccessible(f);
    smartSet(f, null, value);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}
  
static Field set_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & java.lang.reflect.Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
}

static Field set_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
}


static Method findMethod_cached(Object o, String method, Object... args) { try {
  if (o == null) return null;
  if (o instanceof Class) {
    _MethodCache cache = callOpt_getCache(((Class) o));
    List<Method> methods = cache.cache.get(method);
    if (methods != null) for (Method m : methods)
      if (isStaticMethod(m) && findMethod_checkArgs(m, args, false))
        return m;
    return null;
  } else {
    _MethodCache cache = callOpt_getCache(o.getClass());
    List<Method> methods = cache.cache.get(method);
    if (methods != null) for (Method m : methods)
      if (findMethod_checkArgs(m, args, false))
        return m;
    return null;
  }
} catch (Exception __e) { throw rethrow(__e); } }

static void smartSet(Field f, Object o, Object value) throws Exception {
  try {
    f.set(o, value);
  } catch (Exception e) {
    Class type = f.getType();
    
    // take care of common case (long to int)
    if (type == int.class && value instanceof Long)
      value = ((Long) value).intValue();
    
    if (type == LinkedHashMap.class && value instanceof Map)
      { f.set(o, asLinkedHashMap((Map) value)); return; }
    
    
    throw e;
  }
}


static <A, B> LinkedHashMap<A, B> asLinkedHashMap(Map<A, B> map) {
  if (map instanceof LinkedHashMap) return (LinkedHashMap) map;
  LinkedHashMap<A, B> m = new LinkedHashMap();
  if (map != null) synchronized(collectionMutex(map)) {
    m.putAll(map);
  }
  return m;
}

}