MOD = 10**9+7
N = int(input())
A = list(map(int,input().split()))
f = [1,1,2,6]

if 0 in A:
    print(-1)
    exit()
ans = 1
for i in range(N):
    if A[i] > 3:
        print(MOD)
        exit()
    ans *= A[i] ** f[A[i]]
    if ans > MOD:
        print(MOD)
        exit()
print(MOD%ans)