/* -*- coding: utf-8 -*-
 *
 * 1665.cc:  No.1665 quotient replace - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<bitset>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 1000000;
const int MAX_A = 1000000;
const int MAX_G = 240;

/* typedef */

typedef bitset<MAX_G> bts;

/* global variables */

int cache[MAX_A + 1];

/* subroutines */

int grundy(int a) {
  if (cache[a] >= 0) return cache[a];

  bts bs;
  for (int p = 1; p * p <= a; p++)
    if (a % p == 0) {
      bs.set(grundy(p));
      int q = a / p;
      if (q < a && q != p) bs.set(grundy(q));
    }

  int g = 1;
  for (; bs.test(g); g++);
  return (cache[a] = g);
}

/* main */

int main() {
  memset(cache, -1, sizeof(cache));
  cache[0] = cache[1] = 0;

  int n;
  scanf("%d", &n);

  int nim = 0;
  for (int i = 0; i < n; i++) {
    int ai;
    scanf("%d", &ai);
    //printf("grundy(%d) = %d\n", ai, grundy(ai));
    nim ^= grundy(ai);
  }

  if (nim) puts("white");
  else puts("black");
  return 0;
}