#include //#include using namespace std; //using namespace atcoder; using ll = long long; #define all(A) A.begin(),A.end() using vll = vector; #define rep(i, n) for (long long i = 0; i < (long long)(n); i++) using Graph = vector>; int main() { vector P(1e6+10, -1); rep(i, 1e6 + 10) { P[i] = i; } P[0] = P[1] = -1; rep(p, 1e6 + 10) { if (P[p]==p) { for (ll j = p + p; j <= 1e6 + 4; j += p) { if(P[j]==j)P[j] = p; } } } ll N; cin >> N; ll AN = 0; rep(i, N) { ll A; cin >> A; ll k = 0; while (A != 1) { A /= P[A]; k++; } AN = AN ^ k; } cout << (AN== 0 ? "black" : "white") << endl; }