n = int(input())
alst = list(map(int, input().split()))
x = 0

max_ = 10 ** 4
isprime = [True] * (max_ + 1)
isprime[0] = isprime[1] = False
for i in range(2, int(max_ ** 0.5 + 1)):
    if not isprime[i]:
        continue
    for j in range(i * i, max_ + 1, i):
        isprime[j] = False
primes = []
for i, tf in enumerate(isprime):
    if tf:
        primes.append(i)

for a in alst:
    cnt = 0
    p = 0
    while primes[p] ** 2 <= a:
        while a % primes[p] == 0:
            a //= primes[p]
            cnt += 1
        p += 1
    if a != 1:
        cnt += 1
    x ^= cnt
    
if x == 0:
    print("black")
else:
    print("white")