You are given two integers n and m. Find the \operatorname{MEX} of the sequence n ⊕ 0, n ⊕ 1, …, n ⊕ m. Here, ⊕ is the [bitwise XOR operator](https://en.wikipedia.org/wiki/Bitwise_operation#XOR).

\operatorname{MEX} of the sequence of non-negative integers is the smallest non-negative integer that doesn't appear in this sequence. For example, \operatorname{MEX}(0, 1, 2, 4) = 3, and \operatorname{MEX}(1, 2021) = 0. 

Input

The first line contains a single integer t (1 ≤ t ≤ 30 000) — the number of test cases.

The first and only line of each test case contains two integers n and m (0 ≤ n, m ≤ 10^9).

Output

For each test case, print a single integer — the answer to the problem.

Example

Input


5
3 5
4 6
3 2
69 696
123456 654321


Output


4
3
0
640
530866

Note

In the first test case, the sequence is 3 ⊕ 0, 3 ⊕ 1, 3 ⊕ 2, 3 ⊕ 3, 3 ⊕ 4, 3 ⊕ 5, or 3, 2, 1, 0, 7, 6. The smallest non-negative integer which isn't present in the sequence i. e. the \operatorname{MEX} of the sequence is 4.

In the second test case, the sequence is 4 ⊕ 0, 4 ⊕ 1, 4 ⊕ 2, 4 ⊕ 3, 4 ⊕ 4, 4 ⊕ 5, 4 ⊕ 6, or 4, 5, 6, 7, 0, 1, 2. The smallest non-negative integer which isn't present in the sequence i. e. the \operatorname{MEX} of the sequence is 3.

In the third test case, the sequence is 3 ⊕ 0, 3 ⊕ 1, 3 ⊕ 2, or 3, 2, 1. The smallest non-negative integer which isn't present in the sequence i. e. the \operatorname{MEX} of the sequence is 0.


import java.util.*;
import java.lang.*;
import java.io.*;
import java.math.*;

public class Main
{
    static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            br = new BufferedReader(new
                     InputStreamReader(System.in)); 
        } 
  
        String n() 
        { 
            while (st == null || !st.hasMoreElements()) 
            { 
                try
                { 
                    st = new StringTokenizer(br.readLine()); 
                } 
                catch (IOException  e) 
                { 
                    e.printStackTrace(); 
                } 
            } 
            return st.nextToken(); 
        } 
  
        int ni() 
        { 
            return Integer.parseInt(n()); 
        } 
  
        long nl() 
        { 
            return Long.parseLong(n()); 
        } 
  
        double nd() 
        { 
            return Double.parseDouble(n()); 
        } 
  
        String nline() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine(); 
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    }

   
     public static long[] randomize(long arr[])
    {
        Random rand = new Random();
for (int i = 0; i < arr.length; ++i) {
   int index = rand.nextInt(arr.length - i);
   long tmp = arr[arr.length - 1 - i];
   arr[arr.length - 1 - i] = arr[index];
   arr[index] = tmp;
}

return arr;
    } 

    static long mod = 1000000007;

  
    public static void main (String[] args) throws java.lang.Exception
    {
        FastReader sc = new FastReader();
        StringBuilder fo = new StringBuilder();

        int test=sc.ni();
        
        while(test-->0)
        {

            long n = sc.ni();
            long m = sc.nl()+1;
            long ans =0;
            long l =0, u = n^m;
            while(l<=u)
            {
                long mid = l+(u-l)/2;
                long curr = n^mid;
               // System.out.println(l+" "+u);
                if(curr>= m)
                {
                    u = mid-1;
                    ans = mid;
                }
                else
                    l = mid + 1;
            }

            System.out.println(ans);
         
        }
        
        
        
    }
    
    
    
    
}
