Ksusha is a beginner coder. Today she starts studying arrays. She has array a1, a2, ..., an, 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!

Input

The first line contains integer n (1 ≤ n ≤ 105), showing how many numbers the array has. The next line contains integers a1, a2, ..., an (1 ≤ ai ≤ 109) — the array elements.

Output

Print a single integer — the number from the array, such that all array elements are divisible by it. If such number doesn't exist, print -1.

If there are multiple answers, you are allowed to print any of them.

Examples

Input

3
2 2 4


Output

2


Input

5
2 1 3 1 6


Output

1


Input

3
2 3 5


Output

-1

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class A {
	public static int gcd(int a, int b) {
		if (a == 0)
			return b;
		return gcd(b % a, a);
	}

	public static void main(String[] args) throws Exception {
		int cnt = nextInt();
		int[] ar = new int[cnt];
		ar[0] = nextInt();
		int gcd = ar[0];
		for (int i = 1; i < cnt; i++) {
			ar[i] = nextInt();
			gcd = gcd(gcd, ar[i]);
		}
		for (int i = 0; i < cnt; i++) {
			if (ar[i] == gcd) {
				System.out.println(gcd);
				return;
			}
		}
		System.out.println(-1);
	}

	static BufferedReader br = new BufferedReader(new InputStreamReader(
			System.in));
	static StringTokenizer st = new StringTokenizer("");

	static int nextInt() throws Exception {
		return Integer.parseInt(next());
	}

	static String next() throws Exception {
		while (true) {
			if (st.hasMoreTokens()) {
				return st.nextToken();
			}
			String s = br.readLine();
			if (s == null) {
				return null;
			}
			st = new StringTokenizer(s);
		}
	}
}
