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.*;
import java.io.InputStreamReader; 
import java.util.Scanner; 
import java.util.StringTokenizer; 
import java.util.*;
import java.math.*;
public class Main 
{ 
    static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            br = new BufferedReader(new
                     InputStreamReader(System.in)); 
        } 
  
        String next() 
        { 
            while (st == null || !st.hasMoreElements()) 
            { 
                try
                { 
                    st = new StringTokenizer(br.readLine()); 
                } 
                catch (IOException  e) 
                { 
                    e.printStackTrace(); 
                } 
            } 
            return st.nextToken(); 
        } 
  
        int nextInt() 
        { 
            return Integer.parseInt(next()); 
        } 
  
        long nextLong() 
        { 
            return Long.parseLong(next()); 
        } 
  
        double nextDouble() 
        { 
            return Double.parseDouble(next()); 
        } 
  
        String nextLine() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine();
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    } 
public static void main(String[] args) 
    { 
       Scanner sc=new  Scanner(System.in); 
       StringBuffer sb=new StringBuffer();
       PrintWriter pw=new PrintWriter(new BufferedOutputStream((System.out)),true);
          int t=1; //sc.nextInt();
          while(t-->0)
          { 
              int n=sc.nextInt();
              List<Integer> l=new ArrayList<>();
              for(int i=0;i<n;i++)
              l.add(sc.nextInt());
              int result = l.get(0);
    for (int i = 1; i < n; i++) 
    { 
        result = gcd(l.get(i), result);
        if(result == 1) 
        { 
           result=1;
           break;
        } 
    } 
            if(l.indexOf(result)>=0)
              System.out.println(result);
              else System.out.println(-1);
    }
    }
     static int gcd(int a, int b) 
    { 
    if (a == 0) 
        return b; 
    return gcd(b % a, a); 
    }
} 
  