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.*;
  import java.util.*;
  public class CodeForcesTest {
  	public static void main(String[] args) throws IOException {
          FastReader sc=new FastReader();
          BufferedWriter out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(java.io.FileDescriptor.out), "ASCII"), 512);
  		int T=sc.nextInt();
          for(int t=0;t<T;t++){
  			int mex = sc.nextInt(),xor=sc.nextInt();
  			int x = computeXOR(mex-1);
  			if(x==xor){
  				System.out.println(mex);
  			}
  			else if((mex^x)==xor){
  				System.out.println(mex+2);
  			}
  			else{
  				System.out.println(mex+1);
  			}
  		}
          out.close();
  	}
  	static int computeXOR(int n)
      {
          // If n is a multiple of 4
          if (n % 4 == 0)
              return n;
        
          // If n%4 gives remainder 1
          if (n % 4 == 1)
              return 1;
        
          // If n%4 gives remainder 2
          if (n % 4 == 2)
              return n + 1;
        
          // If n%4 gives remainder 3
          return 0;
      }
      static class FastReader 
  	{ 
  		BufferedReader br; 
  		StringTokenizer st; 
  
  		public FastReader() 
  		{ 
  			br = new BufferedReader(new InputStreamReader(System.in)); 
  		} 
  
  		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; 
  		}
  		int[] readArray(int n){
  			FastReader sc = new FastReader();
  			int[] a = new int[n];
  			for(int i=0;i<n;i++){
  				a[i]=sc.nextInt();
  			}
  			return a;
  		} 
  	} 
  	static int Mex(int[] a){
          Arrays.sort(a);
          if(a[0]!=1){
              return 1;
          }
          for(int i=0;i<a.length-1;i++){
              if(a[i]!=a[i+1] && a[i+1]>a[i]+1){
                  return a[i]+1;
              }
          }
          return a[a.length-1]+1;
      }
  	static int gcd(Integer a,Integer b)
      {
          if(b==0)
              return a;
          else
              return gcd(b,a%b);
      }
  	static boolean isPrime(long n)
      {
   
          // Check if number is less than
          // equal to 1
          if (n <= 1)
              return false;
   
          // Check if number is 2
          else if (n == 2)
              return true;
   
          // Check if n is a multiple of 2
          else if (n % 2 == 0)
              return false;
   
  		// If not, then just check the odds
  		double l = Math.sqrt(n);
          for (int i = 3; i <= l; i += 2) 
          {
              if (n % i == 0)
                  return false;
          }
          return true;
      }
  	static class Edge{
  		int to,weight;
  		public Edge(int to,int weight){
  			this.to=to;
  			this.weight=weight;
  		}
  	}
  }
  