#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int,int>;
#define rep(i, n) for(int i = 0; i < n; i++)
#define all(x) (x).begin(),(x).end()

int main(){
    int MAX_N = 1001001;
    vector<bool> PNJudge(MAX_N,true);
    set<int> pn;
    PNJudge[1] = false;
    for(int i=2;i<MAX_N;i++){
        if(!PNJudge[i]) continue;
        pn.insert(i);
        for(int j=i*2;j<MAX_N;j+=i) PNJudge[j] = false;
    }
    int n;
    cin >> n;
    int pncnt = 0, compcnt = 0;
    rep(i,n){
        int a;
        cin >> a;
        if(pn.count(a)) pncnt++;
        else if(a!=1) compcnt++;
    }
    bool ans;
    if(compcnt) ans = (compcnt & 1);
    else ans = (pncnt & 1);
    if(ans) cout << "white" << endl;
    else cout << "black" << endl;
    return 0;
}