#include <bits/stdc++.h>
using namespace std;

struct osa_k {
private:
	std::vector<int> spf, pr;

public:
	osa_k() = default;

	osa_k(int MAX) : spf(MAX + 1) {
		for(int i = 2; i <= MAX; i++) {
			if(spf[i] == 0) {
				spf[i] = i;
				pr.push_back(i);
			}
			for(int j = 0; j < pr.size() and pr[j] <= spf[i] and i * pr[j] <= MAX; j++)
				spf[i * pr[j]] = pr[j];
		}
	}

	std::vector<std::pair<int, int>> PF(int n) {
		std::vector<std::pair<int, int>> divisor;
		if(n == 1) return divisor;
		int before = spf[n], cnt = 0;
		while(n > 1) {
			if(spf[n] == before) {
				cnt++;
				n /= spf[n];
			} else {
				divisor.emplace_back(before, cnt);
				before = spf[n];
				cnt = 1;
				n /= spf[n];
			}
		}
		divisor.emplace_back(before, cnt);
		return divisor;
	}

	int smallestprimefactor(const int n) const {
		return spf[n];
	}

	bool isPrime(const int n) const {
		return n == spf[n];
	}
};

const int m = 1000000;
osa_k pf(m);
int main() {
	int n;
	cin >> n;
	int fold = 0;
	while(n--) {
		int a;
		cin >> a;
		if(a == 1) continue;
		auto vec = pf.PF(a);
		int tmp = 0;
		for(auto [val, cnt] : vec) tmp = max(tmp, cnt);
		fold ^= ((int)vec.size() == 1 ? tmp : tmp + 1);
	}
	cout << (fold ? "white" : "black") << '\n';
	return 0;
}