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

def kaijo(n):
    ret = 1
    for i in range(1,n+1):
        ret *= i
    return ret

#print(A)

ans = 1
for a in A:
    if a == 0:
        print(-1)
        exit()
    if a >= 4:
        print(mod)
        exit()
    ans *= pow(a,kaijo(a))
    
print(mod%ans)