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.
#!/usr/bin/env python
# coding=utf-8
'''
Author: Deean
Date: 2021-11-12 23:29:09
LastEditTime: 2021-11-12 23:42:29
Description: Ksusha and Array
FilePath: CF299A.py
'''


def func():
    n = int(input())
    num = list(set(map(int, input().strip().split())))
    for i in range(len(num)):
        for j in range(len(num)):
            if num[j] % num[i] != 0:
                break
        else:
            return num[i]
    return -1
    

if __name__ == '__main__':
    ans = func()
    print(ans)
    