description: Alice gave Bob two integers a and b (a > 0 and b ≥ 0). Being a curious boy, Bob wrote down an array of non-negative integers with \operatorname{MEX} value of all elements equal to a and \operatorname{XOR} value of all elements equal to b.
  
  What is the shortest possible length of the array Bob wrote?
  
  Recall that the \operatorname{MEX} (Minimum EXcluded) of an array is the minimum non-negative integer that does not belong to the array and the \operatorname{XOR} of an array is the [bitwise XOR](https://en.wikipedia.org/wiki/Bitwise_operation#XOR) of all the elements of the array.
  
  Input
  
  The input consists of multiple test cases. The first line contains an integer t (1 ≤ t ≤ 5 ⋅ 10^4) — the number of test cases. The description of the test cases follows.
  
  The only line of each test case contains two integers a and b (1 ≤ a ≤ 3 ⋅ 10^5; 0 ≤ b ≤ 3 ⋅ 10^5) — the \operatorname{MEX} and \operatorname{XOR} of the array, respectively.
  
  Output
  
  For each test case, output one (positive) integer — the length of the shortest array with \operatorname{MEX} a and \operatorname{XOR} b. We can show that such an array always exists.
  
  Example
  
  Input
  
  
  5
  1 1
  2 1
  2 0
  1 10000
  2 10000
  
  
  Output
  
  
  3
  2
  3
  2
  3
  
  Note
  
  In the first test case, one of the shortest arrays with \operatorname{MEX} 1 and \operatorname{XOR} 1 is [0, 2020, 2021].
  
  In the second test case, one of the shortest arrays with \operatorname{MEX} 2 and \operatorname{XOR} 1 is [0, 1].
  
  It can be shown that these arrays are the shortest arrays possible.
solution: import java.io.OutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.PrintWriter;
  import java.io.PrintStream;
  import java.util.ArrayList;
  import java.io.InputStream;
  
  /**
   * Built using CHelper plug-in
   * Actual solution is at the top
   *
   * @author Sherlock108
   */
  public class Main {
      public static void main(String[] args) {
          InputStream inputStream = System.in;
          OutputStream outputStream = System.out;
          FastReader in = new FastReader(inputStream);
          PrintWriter out = new PrintWriter(outputStream);
          BMEXorMixup solver = new BMEXorMixup();
          int testCount = Integer.parseInt(in.next());
          for (int i = 1; i <= testCount; i++)
              solver.solve(i, in, out);
          out.close();
      }
  
      static class BMEXorMixup {
          int[] prefix;
  
          public void solve(int testNumber, FastReader in, PrintWriter out) {
              if (testNumber == 1) createXor();
              int i, j, k;
              int a = in.nextInt(), b = in.nextInt();
              int ans = 0;
              ArrayList<Integer> arr = new ArrayList();
              int xorSoFar = 0;
  //        for (i = 0; i < a; ++i) {
  //            arr.add(i);
  //            xorSoFar = xorSoFar ^ i;
  //        }
              xorSoFar = prefix[a - 1];
              ans = a;
              if (xorSoFar != b) {
                  if ((xorSoFar ^ b) == a) ans += 2;
                  else ans++;
              }
              out.println(ans);
  
          }
  
          public void createXor() {
              prefix = new int[1_000_000];
              for (int i = 1; i < prefix.length; ++i) {
                  prefix[i] = prefix[i - 1] ^ i;
              }
          }
  
      }
  
      static class FastReader {
          static final int BUFSIZE = 1 << 20;
          static byte[] buf;
          static int index;
          static int total;
          static InputStream in;
  
          public FastReader(InputStream is) {
              try {
                  in = is;
                  buf = new byte[BUFSIZE];
              } catch (Exception e) {
              }
          }
  
          private int scan() {
              try {
                  if (index >= total) {
                      index = 0;
                      total = in.read(buf);
                      if (total <= 0)
                          return -1;
                  }
                  return buf[index++];
              } catch (Exception | Error e) {
                  System.err.println(e.getMessage());
                  return 13 / 0;
              }
          }
  
          public String next() {
              int c;
              for (c = scan(); c <= 32; c = scan()) ;
              StringBuilder sb = new StringBuilder();
              for (; c > 32; c = scan())
                  sb.append((char) c);
              return sb.toString();
          }
  
          public int nextInt() {
              int c, val = 0;
              for (c = scan(); c <= 32; c = scan()) ;
              boolean neg = c == '-';
              if (c == '-' || c == '+')
                  c = scan();
              for (; c >= '0' && c <= '9'; c = scan())
                  val = (val << 3) + (val << 1) + (c & 15);
              return neg ? -val : val;
          }
  
      }
  }
  
  