from collections import Counter
#N = 入力の最大
N = 1145140
sieve = [i for i in range(N + 1)]

for i in range(2,N + 1):
    if sieve[i] == i:
        for j in range(2 * i, N + 1, i):
            sieve[j] = i

def prime_fact(X):
    ret = Counter()
    if X == 1:
        return 0
    while 1:
        ret[sieve[X]] += 1
        if sieve[X] == X:
            break
        else:
            X //= sieve[X]
    ans = 0
    for v in ret.values():
        ans += v
    return ans

n = int(input())

a = list(map(int,input().split()))

b = [0] * n 

for i in range(n):
    b[i] = prime_fact(a[i])
x = 0
for i in range(n):
    x ^= b[i]
if x == 0:
    print('black')
else:
    print('white')