#include <bits/stdc++.h>
using namespace std;

int main() {
    int N;
    cin >> N;
    int n = 0;
    for (int _ = 0; _ < N; _++) {
        int a;
        cin >> a;
        int cnt = 0;
        for (int i = 2; i*i <= a; i++) {
            while (a % i == 0) {
                a /= i;
                cnt++;
            }
        }
        if (a != 1) cnt++;
        n ^= cnt;
    }

    if (n) cout << "white" << endl;
    else cout << "black" << endl;
}