#include <bits/stdc++.h>
#define rep(i, l, r) for (int i = (l); i < (r); i++)
using namespace std;

typedef long long ll;

int main() {
    vector<int> B(1000001, 0);
    rep(i, 2, 1000001) {
        for (int j = 2; j * j <= i; j++) {
            if (i % j == 0) {
                B[i] = B[i / j] + 1;
                break;
            }
        }
        if (B[i] == 0) B[i] = 1;
    }
    int N, A, X = 0;
    cin >> N;
    rep(i, 0, N) {
        cin >> A;
        X ^= B[A];
        //cout << X << " " << B[A] << endl;
    }
    if (X == 0) cout << "black" << endl;
    else cout << "white" << endl;
}