import math
def prime_numbers(x: int) -> list:
    if x < 2:
        return []

    prime_numbers = [i for i in range(x)]
    prime_numbers[1] = 0

    for prime_number in prime_numbers:
        if prime_number ** 2 > x:
            break

        if prime_number == 0:
            continue

        for composite_number in range(2 * prime_number, x, prime_number):
            prime_numbers[composite_number] = 0

    return [prime_number for prime_number in prime_numbers if prime_number != 0]
primes = prime_numbers(10 ** 4)
def prime_factorize(n):
	a = []
	tmp = n
	for i in primes:
		if i ** 2 > n: break
		while tmp % i == 0:
			tmp //= i
			a.append(i)
	if tmp != 1: a.append(tmp)
	return a

n = int(input())
a = list(map(int, input().split()))
b = []
for i in a:
	b.append(len(prime_factorize(i)))
ans = 0
for i in b:
	ans ^= i
print("black" if ans == 0 else "white")