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


n, a = int(input()), list(map(int, input().split()))

if n == 1:
    print(a[0])
else:
    g = math.gcd(a[0], a[1])
    for i in range(2, n):
        g = math.gcd(g, a[i])

    for d in range(1, int(math.sqrt(g)) + 1):
        if g % d == 0:
            if d in a:
                print(d)
                break
            elif g // d in a:
                print(g // d)
                break
    else:
        print(-1)
