n = int(input())
A = list(map(int, input().split()))
mod = 10**9 + 7

if min(A) == 0:
    print(-1)
elif max(A) >= 4:
    print(mod)
else:
    ans = 1
    Fact = [1, 1, 2, 6]
    for i in range(n):
        ans *= pow(A[i], Fact[A[i]])
    print(mod % ans)