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.*;

public class Mikasa implements Runnable {

   void solve() {
      int t = ri();
      while (t-- > 0) {
         int n = ri(), m = ri();
         m++;
         int ans = 0;

         for (int i = 30; i >= 0; i--) {
            int nb = (1 << i) & n;
            int mb = (1 << i) & m;
            if (nb == 0 && mb > 0) {
               ans |= (1 << i);
            } else if (nb > 1 && mb == 0) {
               break;
            }
         }
         println(ans);
      }
   }

   /************************************************************************************************************************************************/
   public static void main(String[] args) throws IOException {
      new Thread(null, new Mikasa(), "1").start();
   }

   static PrintWriter out = new PrintWriter(System.out);
   static Reader read = new Reader();
   static StringBuilder sbr = new StringBuilder();
   static int mod = (int) 1e9 + 7;
   static int dmax = Integer.MAX_VALUE;
   static long lmax = Long.MAX_VALUE;
   static int dmin = Integer.MIN_VALUE;
   static long lmin = Long.MIN_VALUE;
   static int[] dprimes = new int[] { 1, 11, 101, 1087, 99991, 100001, 1000003, 15485863, 999999937 };

   @Override
   public void run() {
      solve();
      out.close();
   }

   static class Reader {
      private byte[] buf = new byte[1024];
      private int index;
      private InputStream in;
      private int total;

      public Reader() {
         in = System.in;
      }

      public int scan() throws IOException {
         if (total < 0)
            throw new InputMismatchException();
         if (index >= total) {
            index = 0;
            total = in.read(buf);
            if (total <= 0)
               return -1;
         }
         return buf[index++];
      }

      public int intNext() throws IOException {
         int integer = 0;
         int n = scan();
         while (isWhiteSpace(n))
            n = scan();
         int neg = 1;
         if (n == '-') {
            neg = -1;
            n = scan();
         }
         while (!isWhiteSpace(n)) {
            if (n >= '0' && n <= '9') {
               integer *= 10;
               integer += n - '0';
               n = scan();
            } else
               throw new InputMismatchException();
         }
         return neg * integer;
      }

      public double doubleNext() throws IOException {
         double doub = 0;
         int n = scan();
         while (isWhiteSpace(n))
            n = scan();
         int neg = 1;
         if (n == '-') {
            neg = -1;
            n = scan();
         }
         while (!isWhiteSpace(n) && n != '.') {
            if (n >= '0' && n <= '9') {
               doub *= 10;
               doub += n - '0';
               n = scan();
            } else
               throw new InputMismatchException();
         }
         if (n == '.') {
            n = scan();
            double temp = 1;
            while (!isWhiteSpace(n)) {
               if (n >= '0' && n <= '9') {
                  temp /= 10;
                  doub += (n - '0') * temp;
                  n = scan();
               } else
                  throw new InputMismatchException();
            }
         }
         return doub * neg;
      }

      public String read() throws IOException {
         StringBuilder sb = new StringBuilder();
         int n = scan();
         while (isWhiteSpace(n))
            n = scan();
         while (!isWhiteSpace(n)) {
            sb.append((char) n);
            n = scan();
         }
         return sb.toString();
      }

      public String rline() throws IOException {
         StringBuilder sb = new StringBuilder();
         int n = scan();
         while (n != '\n') {
            sb.append((char) n);
            n = scan();
         }
         return sb.toString();
      }

      private boolean isWhiteSpace(int n) {
         if (n == ' ' || n == '\n' || n == '\r' || n == '\t' || n == -1)
            return true;
         return false;
      }
   }

   static void print(Object object) {
      out.print(object);
   }

   static void println(Object object) {
      out.println(object);
   }

   static int[] iArr(int len) {
      return new int[len];
   }

   static long[] lArr(int len) {
      return new long[len];
   }

   static long min(long a, long b) {
      return Math.min(a, b);
   }

   static int min(int a, int b) {
      return Math.min(a, b);
   }

   static long max(Long a, Long b) {
      return Math.max(a, b);
   }

   static int max(int a, int b) {
      return Math.max(a, b);
   }

   static int ri() {
      try {
         return read.intNext();
      } catch (IOException e) {
         e.printStackTrace();
      }
      System.exit(2);
      return -1;
   }

   static long rl() {
      try {
         return Long.parseLong(read.read());
      } catch (IOException e) {
         e.printStackTrace();
      }
      System.exit(2);
      return -1;
   }

   static String rs() {
      try {
         return read.read();
      } catch (IOException e) {
         e.printStackTrace();
      }
      System.exit(2);
      return "";
   }

   static String rline() {
      try {
         return read.rline();
      } catch (IOException e) {
         e.printStackTrace();
      }
      System.exit(2);
      return "";
   }

   static char rc() {
      return rs().charAt(0);
   }

   static double rd() {
      try {
         return read.doubleNext();
      } catch (IOException e) {
         e.printStackTrace();
      }
      System.exit(2);
      return -1;
   }
}
