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.
import math
def divisible(nums):
    if len(nums) < 2:
        return None 
    gcd = math.gcd(nums[0], nums[1])
    for i in range(2,len(nums)):
        gcd = math.gcd(gcd,nums[i])
    return gcd 




T = int(input())
nums = list(map(int,input().split()))
nums = list(sorted(set(nums)))
result = divisible(nums)
if (result == 1):
    if 1 in nums:
        result = 1 
    else:
        result = -1 
print(result)
    
    

		 		     				  		  	 					 	