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.*; class main { static IntegerIterator integerIterator(int[] l) { return l == null ? null : new IntegerIterator() { int i = 0; public boolean hasNext() { return i < l.length; } public int next() { return l[i++]; } }; } abstract static class IntegerIterator { abstract boolean hasNext(); abstract int next(); } }