Ksusha is a beginner coder. Today she starts studying arrays. She has array *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub>, consisting of *n* positive integers.

Her university teacher gave her a task. Find such number in the array, that all array elements are divisible by it. Help her and find the number!
The first line contains integer *n* (1 ≤ *n* ≤ 10<sup class="upper-index">5</sup>), showing how many numbers the array has. The next line contains integers *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> (1 ≤ *a*<sub class="lower-index">*i*</sub> ≤ 10<sup class="upper-index">9</sup>) — the array elements.
def gcd(a,b):
    if(b == 0):
        return a
    t =a
    a = b
    b= t%a
    return gcd(a,b)

def main():
   n = input()
   l = list(map(int,input().split()))
   g = 0
   for i in l:
       g = gcd(g,i)
   if(g in l):
       print(g)
   else:
       print(-1)
main()
   		 		 			    			  	 		 			