#include "bits/stdc++.h"
//#include "atcoder/all"
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
//const bool debug = false;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define endl "\n"
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
int v[1000006];
void sieve() {
	v[1] = 1;
	for (int i = 2; i <= 1000000; ++i) {
		if (0 != v[i])continue;
		v[i] = i;
		for (int j = i * 2; j <= 1000000; j += i) {
			if (0 == v[j]) v[j] = i;
		}
	}
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n; cin >> n;
	sieve();
	int nim = 0;
	while (n--) {
		int a; cin >> a;
		int c = 0;
		while (a != 1) {
			a = a / v[a];
			c++;
		}
		nim ^= c;
	}
	cout << (nim ? "white" : "black") << endl;
	return 0;
}