def num_divisors(n):
    divisors = []
    for i in range(1, int(n**0.5)+1):
        if n % i == 0:
            divisors.append(i)
            if i != n // i:
                divisors.append(n//i)
    return len(divisors) - 1

N = int(input())
A = list(map(int,input().split()))
G = 0
for i in range(N):
    G ^= num_divisors(A[i])
if G == 0:
    print("black")
else:
    print("white")