import java.util.*;
import java.util.concurrent.*;

// Elimination array provides a list of exchangers which
// are picked at random for a given value.

class EliminationArray {
  Exchanger[] exchangers;
  final long TIMEOUT;
  final TimeUnit UNIT;
  Random random;
  // exchangers: array of exchangers
  // TIMEOUT: exchange timeout number
  // UNIT: exchange timeout unit
  // random: random number generator

  @SuppressWarnings("unchecked")
  public EliminationArray(int capacity, long timeout, TimeUnit unit) {
    exchangers = new Exchanger[capacity];
    for (int i=0; i