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.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.StringTokenizer;
import java.util.TreeMap;
import java.util.Map.Entry;


public class main {
	private static BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
	private static BufferedWriter w=new BufferedWriter(new OutputStreamWriter(System.out));
	
	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub
		int t=Integer.parseInt(br.readLine());

		while(t>0) {
		    StringTokenizer st = new StringTokenizer(br.readLine());
		    long n=Long.parseLong(st.nextToken());
		    long m=Long.parseLong(st.nextToken());
		    if(m<n) {
		    	w.write(0+"\n");
		    }
		    else {
		    	String res=calc(n, m+1);
		    	long ans=Long.parseLong(res, 2);
		    	w.write(ans+"\n");
		    }
			t--;
		}
		w.flush();
		w.close();
	}
    public static String calc(long n,long m) {
    	String s1=Long.toBinaryString(n);
    	String s2=Long.toBinaryString(m);
    	//make lengths equal;
    	while(s1.length()<s2.length()) {
    		s1=0+s1;
    	}
    //	System.out.println(s1+" "+s2);
    	int i=0;
    	String res="";
    	while(i<s1.length()) {
    		int b1=Integer.parseInt(s1.charAt(i)+"");
    		int b2=Integer.parseInt(s2.charAt(i)+"");
    		if(b1==b2) {
    			res+=0;
    		}
    		else if(b1==0 && b2==1) {
    			res+=1;
    		}
    		else {
    			//found mex
    			int zeroes=s1.length()-res.length();
    			res+=("0").repeat(zeroes);
    			break;
    		}
    		i++;
    	}
    	return res;
    }
}