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 C {
	public static void main(String[] args) throws IOException {
		Kattio io = new Kattio();

		int t = io.nextInt();

		for (int ii=0; ii<t; ii++) {
			long n = io.nextInt();
			long m = io.nextInt();

			long ans = Long.MAX_VALUE;
			
			for (int i=31; i>=0; i--) {
				long aa = (n>>i)<<i; 
				long bb = ((m>>i)+1)<<i;
				ans = Math.min(ans, aa^bb);
			}

			io.println(ans);
		}
		io.close();
	}

	static class Kattio extends PrintWriter {
		private BufferedReader r;
		private StringTokenizer st;

		// standard input
		public Kattio() { this(System.in, System.out); }
		public Kattio(InputStream i, OutputStream o) {
			super(o);
			r = new BufferedReader(new InputStreamReader(i));
		}
		// USACO-style file input
		public Kattio(String problemName) throws IOException {
			super(new FileWriter(problemName + ".out"));
			r = new BufferedReader(new FileReader(problemName + ".in"));
		}

		// returns null if no more input
		public String next() {
			try {
				while (st == null || !st.hasMoreTokens())
					st = new StringTokenizer(r.readLine());
				return st.nextToken();
			} catch (Exception e) { }
			return null;
		}

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