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.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.File;
  import java.io.*;
  import java.util.*;
  
  public class Main {
  
      // static final File ip = new File("input.txt");
      // static final File op = new File("output.txt");
      // static {
      //     try {
      //         System.setOut(new PrintStream(op));
      //         System.setIn(new FileInputStream(ip));
      //     } catch (Exception e) {
      //     }
      // }
  
      static int computeXOR(int n) {
  
          if (n % 4 == 0)
              return n;
  
          if (n % 4 == 1)
              return 1;
  
          if (n % 4 == 2)
              return n + 1;
  
          return 0;
      }
  
      public static void main(String[] args) {
          FastReader sc = new FastReader();
          int test = sc.nextInt();
          while (test-- != 0) {
              int a = sc.nextInt();
              int b = sc.nextInt();
              int xor = computeXOR(a - 1);
              if (xor == b)
                  System.out.println(a);
              else if ((xor ^ b) == a)
                  System.out.println(a + 2);
              else
                  System.out.println(a + 1);
          }
      }
  
      static long power(long x, long y, long p) {
          long res = 1;
          x = x % p;
          if (x == 0)
              return 0;
          while (y > 0) {
              if ((y & 1) != 0)
                  res = (res * x) % p;
              y = y >> 1;
              x = (x * x) % p;
          }
          return res;
      }
  
      public static int countSetBits(long number) {
          int count = 0;
          while (number > 0) {
              ++count;
              number &= number - 1;
          }
          return count;
      }
  
      private static <T> void swap(int[] a, int i, int j) {
          int tmp = a[i];
          a[i] = a[j];
          a[j] = tmp;
      }
  
      static class pair {
          long a, b;
  
          pair(long x, long y) {
              this.a = x;
              this.b = y;
          }
          // public boolean equals(Object o) {
          // if (this == o) return true;
          // if (!(o instanceof pair)) return false;
          // pair key = (pair) o;
          // return a == key.a && b == key.b;
          // }
  
          // @Override
          // public int hashCode() {
          // int result = a;
          // result = 31 * result + b;
          // return result;
          // }
  
          // public int compare(pair p1, pair p2) {
          // if(p1.a - p2.a > 0) return -1;
          // if(p1.a - p2.a < 0) return 1;
          // return 0;
          // }
      }
  
      static class comparator implements Comparator<pair> {
  
          public int compare(pair p1, pair p2) {
              if (p1.a - p2.a > 0)
                  return 1;
              if (p1.a - p2.a < 0)
                  return -1;
              if (p1.a == p2.a) {
                  if (p1.b > p2.b)
                      return -1;
                  else if (p1.b < p2.b)
                      return 1;
              }
              return 0;
          }
      }
  
      private static long getSum(int[] array) {
          long sum = 0;
          for (int value : array) {
              sum += value;
          }
          return sum;
      }
  
      private static boolean isPrime(Long x) {
          if (x < 2)
              return false;
          for (long d = 2; d * d <= x; ++d) {
              if (x % d == 0)
                  return false;
          }
          return true;
      }
  
      static int[] reverse(int a[], int n) {
          int i, k, t;
          for (i = 0; i < n / 2; i++) {
              t = a[i];
              a[i] = a[n - i - 1];
              a[n - i - 1] = t;
          }
          return a;
      }
  
      private static boolean isPrimeInt(int x) {
          if (x < 2)
              return false;
          for (int d = 2; d * d <= x; ++d) {
              if (x % d == 0)
                  return false;
          }
          return true;
      }
  
      public static String reverse(String input) {
          StringBuilder str = new StringBuilder("");
  
          for (int i = input.length() - 1; i >= 0; i--) {
              str.append(input.charAt(i));
          }
  
          return str.toString();
      }
  
      private static int[] getPrimes(int n) {
          boolean[] used = new boolean[n + 1];
          used[0] = used[1] = true;
          int size = 0;
          for (int i = 2; i <= n; ++i) {
              if (!used[i]) {
                  ++size;
                  for (int j = 2 * i; j <= n; j += i) {
                      used[j] = true;
                  }
              }
          }
          int[] primes = new int[size];
          for (int i = 0, cur = 0; i <= n; ++i) {
              if (!used[i]) {
                  primes[cur++] = i;
              }
          }
          return primes;
      }
  
      private static long lcm(long a, long b) {
          return a / gcd(a, b) * b;
      }
  
      private static long gcd(long a, long b) {
          return (a == 0 ? b : gcd(b % a, a));
      }
  
      static void sortI(int[] arr) {
          int n = arr.length;
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              int tmp = arr[i];
              int randomPos = i + rnd.nextInt(n - i);
              arr[i] = arr[randomPos];
              arr[randomPos] = tmp;
          }
          Arrays.sort(arr);
      }
  
      static void shuffleList(ArrayList<Long> arr) {
          int n = arr.size();
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              long tmp = arr.get(i);
              int randomPos = i + rnd.nextInt(n - i);
              arr.set(i, arr.get(randomPos));
              arr.set(randomPos, tmp);
          }
      }
  
      static void factorize(long n) {
          int count = 0;
          while (!(n % 2 > 0)) {
              n >>= 1;
  
              count++;
          }
          if (count > 0) {
              // System.out.println("2" + " " + count);
          }
          long i = 0;
          for (i = 3; i <= (long) Math.sqrt(n); i += 2) {
              count = 0;
              while (n % i == 0) {
                  count++;
                  n = n / i;
              }
              if (count > 0) {
                  // System.out.println(i + " " + count);
              }
          }
  
          if (n > 2) {
              // System.out.println(i + " " + count);
          }
      }
  
      static void sortL(long[] arr) {
          int n = arr.length;
          Random rnd = new Random();
          for (int i = 0; i < n; ++i) {
              long tmp = arr[i];
              int randomPos = i + rnd.nextInt(n - i);
              arr[i] = arr[randomPos];
              arr[randomPos] = tmp;
          }
          Arrays.sort(arr);
      }
  
      static class FastReader {
          BufferedReader br;
          StringTokenizer st;
  
          public FastReader() {
              br = new BufferedReader(new InputStreamReader(System.in));
          }
  
          public boolean hasNext() {
              return false;
          }
  
          String next() {
              while (st == null || !st.hasMoreElements()) {
                  try {
                      st = new StringTokenizer(br.readLine());
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              }
              return st.nextToken();
          }
  
          int nextInt() {
              return Integer.parseInt(next());
          }
  
          long nextLong() {
              return Long.parseLong(next());
          }
  
          double nextDouble() {
              return Double.parseDouble(next());
          }
  
          String nextLine() {
              String str = "";
              try {
                  str = br.readLine();
              } catch (IOException e) {
                  e.printStackTrace();
              }
              return str;
          }
      }
  }