description: Alice and Borys are playing tennis.
  
  A tennis match consists of games. In each game, one of the players is serving and the other one is receiving.
  
  Players serve in turns: after a game where Alice is serving follows a game where Borys is serving, and vice versa.
  
  Each game ends with a victory of one of the players. If a game is won by the serving player, it's said that this player holds serve. If a game is won by the receiving player, it's said that this player breaks serve.
  
  It is known that Alice won a games and Borys won b games during the match. It is unknown who served first and who won which games.
  
  Find all values of k such that exactly k breaks could happen during the match between Alice and Borys in total.
  
  Input
  
  Each test contains multiple test cases. The first line contains the number of test cases t (1 ≤ t ≤ 10^3). Description of the test cases follows.
  
  Each of the next t lines describes one test case and contains two integers a and b (0 ≤ a, b ≤ 10^5; a + b > 0) — the number of games won by Alice and Borys, respectively.
  
  It is guaranteed that the sum of a + b over all test cases does not exceed 2 ⋅ 10^5.
  
  Output
  
  For each test case print two lines.
  
  In the first line, print a single integer m (1 ≤ m ≤ a + b + 1) — the number of values of k such that exactly k breaks could happen during the match.
  
  In the second line, print m distinct integers k_1, k_2, …, k_m (0 ≤ k_1 < k_2 < … < k_m ≤ a + b) — the sought values of k in increasing order.
  
  Example
  
  Input
  
  
  3
  2 1
  1 1
  0 5
  
  
  Output
  
  
  4
  0 1 2 3
  2
  0 2
  2
  2 3
  
  Note
  
  In the first test case, any number of breaks between 0 and 3 could happen during the match: 
  
    * Alice holds serve, Borys holds serve, Alice holds serve: 0 breaks; 
    * Borys holds serve, Alice holds serve, Alice breaks serve: 1 break; 
    * Borys breaks serve, Alice breaks serve, Alice holds serve: 2 breaks; 
    * Alice breaks serve, Borys breaks serve, Alice breaks serve: 3 breaks. 
  
  
  
  In the second test case, the players could either both hold serves (0 breaks) or both break serves (2 breaks).
  
  In the third test case, either 2 or 3 breaks could happen: 
  
    * Borys holds serve, Borys breaks serve, Borys holds serve, Borys breaks serve, Borys holds serve: 2 breaks; 
    * Borys breaks serve, Borys holds serve, Borys breaks serve, Borys holds serve, Borys breaks serve: 3 breaks. 
solution: import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.*;
  public class charmedByGame {
  
  	public static void main(String[] args) {
  
  //		Scanner sc = new Scanner(System.in);
  		FastReader sc= new FastReader();
  		int t = sc.nextInt();
  		for(int o = 0 ; o<t;o++) {
  			int a = sc.nextInt();
  			int b = sc.nextInt();
  			
  			if((a+b)%2==0) {
  				int n = (a + b)/2;
  				int x = Math.max(a, b);
  				int y = Math.min(a, b);
  				System.out.println(y +1);
  				
  				for(int i = 0 ; i<=y;i++) {
  					System.out.print(x + 2 * i - n + " ");
  				}
  				System.out.println();
  			}else {
  				ArrayList<Integer> al = new ArrayList<>();
  				int x = Math.max(a, b);
  				int y = Math.min(a, b);
  				int n = (a+b)/2;
  				int m = (a+b)/2 +1;
  				for(int i = 0 ; i<=y;i++) {
  //					System.out.print(x + 2 * i - n + " ");
  				al.add(x + 2 * i - n);
  				}
  				for(int i = 0 ; i<=y;i++) {
  //					System.out.print(x + 2 * i - n + " ");
  				al.add(x + 2 * i - m);
  				}
  				
  				Collections.sort(al);
  				System.out.println(al.size());
  				for(int p : al) {
  					System.out.print(p + " ");
  					
  				}
  			System.out.println();
  			}
  			
  		}
  		
  	}
  
  }
  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;
      }
  }
  