import math

n = int(input())
a = list(map(int,input().split()))
ans = 1
#b = 1
for i in range(n):
  tmp1 = math.factorial(a[i])
  tmp2 = (a[i]**tmp1)
  ans = tmp2*ans
  #b *= (a[i]**(math.factorial(a[i])))
  
#print(b)
if ans > 0:
  print(((10**9)+7)%ans)
else:
  print(-1)