n = int(input())
A = list(map(int, input().split()))

P = [0 for _ in range(n)]
for i in range(n):
    m = A[i]
    while m % 2 == 0:
        P[i] += 1
        m //= 2
    f = 3
    while f * f <= A[i]:
        while m % f == 0:
            P[i] += 1
            m //= f
        f += 2
    if m != 1:
        P[i] += 1

state = 0
for i in range(n):
    state ^= P[i]

if state == 0:
    print("black")
else:
    print("white")