#include <iostream>
using namespace std;
int main(){
    int n;cin>>n;
    int nw = 0;
    for(int i = 0; n > i; i++){
        int a;cin>>a;
        int k = 0;
        for(int j = 2; a >= j*j; j++){
            while(a%j == 0){
                a/=j;
                k++;
            }
        }
        if(a!=1)k++;
        nw ^= k;
    }
    if(nw == 0){
        cout << "black" << endl;
    }else{
        cout << "white" << endl;
    }
}