#include <iostream>
using namespace std;

int A[100009];
int x = 0;
int N;

int factorize(int x){
    int cnt = 0;
    int temp = x;
    for (int i = 2; i * i <= x; i++){
        if (temp % i == 0){
            while (temp % i == 0) {
                temp = temp / i;
                cnt++;
            }
        }
    if (temp != 1){
        cnt++;
    }
    }
    return cnt;
}

int main(){
    cin >> N;
    for (int i = 0; i < N; i++){
        cin >> A[i];
    }
    for (int i = 0; i < N; i++){
        int cnt;
        cnt = factorize(A[i]);
        x ^= cnt;
    }
    if (x == 0){
        cout << "black" << endl;
    }
    else{
        cout << "white" << endl;
    }
    return 0;
}