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 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.*;
public class main {
public static void main(String[] args) throws Exception {
String s = "Hello world world world";
print("Original:\n " + s);
String transformed = bwt(s, '|');
print("BWT Transformed:\n " + transformed);
String x = inverseBWT(transformed, '|');
print("Transformed back:\n " + x);
print(eq(s, x) ? "Yo!" : "No...");
print();
// Transform it again
String doublyTransformed = bwt(transformed, '^');
print("Doubly Transformed (not very useful):\n " + doublyTransformed);
}
static String bwt(String input, char endMarker) {
input += endMarker;
int n = l(input);
String[] tbl = new String[n];
for (int i = 0; i < n; i++)
tbl[i] = rotateString(input, i);
sort(tbl);
StringBuilder buf = new StringBuilder();
for (int i = 0; i < n; i++)
buf.append(last(tbl[i]));
return str(buf);
}
static String rotateString(String s, int n) {
if (n == 0) return s;
return substring(s, l(s)-n) + substring(s, 0, l(s)-n);
}
static String inverseBWT(String s, char endMarker) {
int n = l(s);
String[] tbl = new String[n];
for (int i = 0; i < n; i++)
tbl[i] = "";
for (int i = 0; i < n; i++) {
// insert
for (int j = 0; j < n; j++)
tbl[j] = s.charAt(j) + tbl[j];
// sort
sort(tbl);
}
for (int i = 0; i < n; i++)
if (last(tbl[i]) == endMarker)
return dropLast(tbl[i]);
throw fail("NEVER FAIL in a perfect world!");
}
static String str(Object o) {
return String.valueOf(o);
}
static String[] dropLast(String[] a, int n) {
n = Math.min(n, a.length);
String[] b = new String[a.length-n];
System.arraycopy(a, 0, b, 0, b.length);
return b;
}
static List dropLast(List l) {
return subList(l, 0, l(l)-1);
}
static String dropLast(String s) {
return substring(s, 0, l(s)-1);
}
static RuntimeException fail() {
throw new RuntimeException("fail");
}
static RuntimeException fail(Object msg) {
throw new RuntimeException(String.valueOf(msg));
}
static RuntimeException fail(String msg) {
throw new RuntimeException(unnull(msg));
}
// disabled for now to shorten some programs
/*static RuntimeException fail(S msg, O... args) {
throw new RuntimeException(format(msg, args));
}*/
static volatile StringBuffer local_log = new StringBuffer(); // not redirected
static volatile StringBuffer 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 int print_maxLineLength = 0; // 0 = unset
static boolean print_silent; // total mute if set
static void print() {
print("");
}
// slightly overblown signature to return original object...
static A print(A o) {
if (print_silent) return o;
String s = String.valueOf(o) + "\n";
// TODO if (print_maxLineLength != 0)
StringBuffer loc = local_log;
StringBuffer 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);
return o;
}
static void print(long l) {
print(String.valueOf(l));
}
static void print(char c) {
print(String.valueOf(c));
}
static void print_append(StringBuffer buf, String s, int max) {
synchronized(buf) {
buf.append(s);
max /= 2;
if (buf.length() > max) 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);
}
}
}
static A last(List l) {
return l.isEmpty() ? null : l.get(l.size()-1);
}
static char last(String s) {
return empty(s) ? '#' : s.charAt(l(s)-1);
}
static void sort(T[] a, Comparator super T> c) {
Arrays.sort(a, c);
}
static void sort(T[] a) {
Arrays.sort(a);
}
static void sort(List a, Comparator super T> c) {
Collections.sort(a, c);
}
static void sort(List a) {
Collections.sort(a);
}
static boolean eq(Object a, Object b) {
if (a == null) return b == null;
if (a.equals(b)) return true;
if (a instanceof BigInteger) {
if (b instanceof Integer) return a.equals(BigInteger.valueOf((Integer) b));
if (b instanceof Long) return a.equals(BigInteger.valueOf((Long) b));
}
return false;
}
static int l(Object[] a) { return a == null ? 0 : a.length; }
static int l(byte[] 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(char[] a) { return a == null ? 0 : a.length; }
static int l(Collection c) { return c == null ? 0 : c.size(); }
static int l(Map m) { return m == null ? 0 : m.size(); }
static int l(CharSequence s) { return s == null ? 0 : s.length(); }
static int l(Object o) {
return l((List) o); // incomplete
}
static String substring(String s, int x) {
return safeSubstring(s, x);
}
static String substring(String s, int x, int y) {
return safeSubstring(s, x, y);
}
static List subList(List l, int startIndex) {
return subList(l, startIndex, l(l));
}
static List subList(List l, int startIndex, int endIndex) {
startIndex = max(0, min(l(l), startIndex));
endIndex = max(0, min(l(l), endIndex));
if (startIndex > endIndex) return litlist();
return l.subList(startIndex, endIndex);
}
static String unnull(String s) {
return s == null ? "" : s;
}
static List unnull(List l) {
return l == null ? emptyList() : l;
}
static Iterable unnull(Iterable i) {
return i == null ? emptyList() : i;
}
static Object[] unnull(Object[] a) {
return a == null ? new Object[0] : a;
}
static boolean empty(Collection c) {
return isEmpty(c);
}
static boolean empty(String s) {
return isEmpty(s);
}
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);
throw fail("unknown type for 'empty': " + getType(o));
}
// hopefully covers all cases :)
static String safeSubstring(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 String safeSubstring(String s, int x) {
return safeSubstring(s, x, l(s));
}
static int max(int a, int b) {
return Math.max(a, b);
}
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 int max(Collection 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 byte max(byte[] c) {
byte x = -128;
for (byte d : c) if (d > x) x = d;
return x;
}
static boolean isEmpty(Collection c) {
return c == null || c.isEmpty();
}
static boolean isEmpty(CharSequence s) {
return s == null || s.length() == 0;
}
static boolean isEmpty(Object[] a) {
return a == null || a.length == 0;
}
static boolean isEmpty(Map map) {
return map == null || map.isEmpty();
}
static List emptyList() {
return new ArrayList();
//ret Collections.emptyList();
}
static int min(int a, int b) {
return Math.min(a, b);
}
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 byte min(byte[] c) {
byte x = 127;
for (byte d : c) if (d < x) x = d;
return x;
}
static String getType(Object o) {
return getClassName(o);
}
static ArrayList litlist(A... a) {
return new ArrayList(Arrays.asList(a));
}
static String getClassName(Object o) {
return o == null ? "null" : o.getClass().getName();
}
}