N = int(input())
A = list(map(int,input().split()))
MOD = 10**9+7
ans = 1
A.sort()
if A[0] < 0:
  print(-1)
elif A[-1] > 3:
  print(MOD)
else:
  for i in range(N):
    ak = 1
    for j in range(1,A[i]+1):
      ak *= j
    ans *= (A[i]**ak)
  print(MOD%ans)