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 Map fieldToFieldIndex(final String fieldA, final String fieldB, Iterable l) {
return pairsToMap((List) collectTwoFieldsAsPair(fieldA, fieldB, l));
}
static HashMap pairsToMap(Collection extends Pair> l) {
HashMap map = new HashMap();
if (l != null) for (Pair p : l)
map.put(p.a, p.b);
return map;
}
static List> collectTwoFieldsAsPair(final String fieldA, final String fieldB, Iterable l) {
return map(l, new F1