from math import factorial
MOD = 10**9 + 7
N = int(input())
A = list(map(int,input().split()))

ans = 1
for e in A:
    if e > 10:
        print(MOD)
        exit(0)
    elif e != 0:
        ans *= pow(e,factorial(e),MOD)
    if ans > MOD:
        print(MOD)
        exit(0)

print(-1 if ans == 0 else MOD%ans)