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.*;
import java.util.StringTokenizer;

public class Main {
    
    public static void main(String[] args) throws IOException {
        Scanner scn = new Scanner(System.in);
        OutputWriter out = new OutputWriter(System.out);
        // Always print a trailing "\n" and close the OutputWriter as shown at the end of your output
        
        // example:
        int t=scn.nextInt();
        for(int i=0;i<t;i++){
        int n=scn.nextInt();
        int m=scn.nextInt();
        int[] arr=new int[2];
        arr[0]=m;arr[1]=n;
        int ans=0;
        while(true){
            int a=msb(m);int b=msb(n);
            if(a==b){
                m-=a;n-=b;
            }
            else if(a>b){
                ans+=a;m-=a;
            }
            else{
                break;
            }
            if(a==0&&b==0){
                ans=med(arr[0]+1,arr[1]);
                break;
            }
        }
        out.print(ans+"\n");
        }
        out.close();
    }
    public static int msb(int n){
        n |= n >> 1;
        n |= n >> 2;
        n |= n >> 4;
        n |= n >> 8;
        n |= n >> 16;
        n = n + 1;
        return (n >> 1);
    }
    public static int med(int m,int n){
        int ans=0;
        while(true){
            int a=msb(m);int b=msb(n);
            if(a==b){
                m-=a;n-=b;
            }
            else if(a>b){
                ans+=a;m-=a;
            }
            else{
                break;
            }
            if(a==0&&b==0){
                break;
            }
        }
        return(ans);
    }

    // fast input
    static class Scanner {
        public BufferedReader reader;
        public StringTokenizer tokenizer;

        public Scanner(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream));
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    String line = reader.readLine();
                    if (line == null)
                        return null;
                    tokenizer = new StringTokenizer(line);
                } catch (Exception e) {
                    throw(new RuntimeException());
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() { return Integer.parseInt(next()); }
        public long nextLong() { return Long.parseLong(next()); }
        public double nextDouble() { return Double.parseDouble(next()); }
    }

    // fast output
    static class OutputWriter {
        BufferedWriter writer;

        public OutputWriter(OutputStream stream) {
            writer = new BufferedWriter(new OutputStreamWriter(stream));
        }

        public void print(int i) throws IOException { writer.write(i); }
        public void print(String s) throws IOException { writer.write(s); }
        public void print(char[] c) throws IOException { writer.write(c); }
        public void close() throws IOException { writer.close(); }
    }


}

