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.
from collections import defaultdict, deque, Counter, OrderedDict
from math import gcd
def main():
    n = int(input())
    g,d = 0,set()
    for i in map(int,input().split()):
        if g == 0: g = i
        else:
            g = gcd(g,i)
        d.add(i)
    print(g if g in d else -1)






if __name__ == "__main__":
    """sys.setrecursionlimit(400000)
    threading.stack_size(40960000)
    thread = threading.Thread(target=main)
    thread.start()"""
    main()