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

public class pre55 {
    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;
        }
    }
    static int integerfrmbinary(String str){
        double j=0;
        for(int i=0;i<str.length();i++){
            if(str.charAt(i)== '1'){
                j=j+ Math.pow(2,str.length()-1-i);
            }

        }
        return (int) j;
    }
    public static void main(String args[]){
        FastReader obj = new FastReader();
        int tc = obj.nextInt();
        while(tc--!=0){
            int n = obj.nextInt(),m = obj.nextInt();
           // System.out.println(Integer.toBinaryString((int)Math.pow(2,30)));
            if(n>m) System.out.println(0);
            else{
                m+=1;
                String ans = "";
                String ns = Integer.toBinaryString(n),ms = Integer.toBinaryString(m);
               // System.out.println(ns+" "+ms);
                while(ns.length()>ms.length()) ms = "0"+ms;
                while(ms.length()>ns.length()) ns = "0"+ns;
              //  System.out.println(ns+" "+ms);
                for(int i=0;i<ms.length();i++){
                    if(ms.charAt(i)=='0' && ns.charAt(i)=='0') ans = "0"+ans;
                    else if(ns.charAt(i)=='1' && ms.charAt(i)=='1') ans ="0"+ans;
                    else if(ns.charAt(i)=='0' && ms.charAt(i)=='1') ans = "1" +ans;
                    else if(ns.charAt(i)=='1' && ms.charAt(i)=='0') {
                        ans = "0"+ans;
                        break;
                    }
                }
                while(ms.length()>ans.length()) ans="0"+ans;
                System.out.println(integerfrmbinary((new StringBuilder(ans)).reverse().toString()));
            }
        }
    }
}
