/**
 *   @FileName	a.cpp
 *   @Author	kanpurin
 *   @Created	2021.09.04 04:06:58
**/

#include "bits/stdc++.h" 
using namespace std; 
typedef long long ll;

int main() {
    int n;cin >> n;
    vector<int> a(1000001);
    vector<int> spf(1000001);
    vector<int> prime;
    for (int d = 2; d <= 1000000; d++) {
        if (a[d] == 0) {
            a[d] = 1;
            spf[d] = d;
            prime.push_back(d);
        }
        for(int p : prime) {
            if (p * d > 1000000 || p > spf[d]) break;
            a[p*d] = a[d] + 1;
            spf[p*d] = p;
        }
    }
    int grundy = 0;
    for (int i = 0; i < n; i++) {
        int t;cin >> t;
        grundy ^= a[t];
    }
    if (grundy == 0) puts("black");
    else puts("white");
    return 0;
}