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: //package com.amoghghadge.compProgramming.Contests;
  
  import java.io.BufferedReader;
  import java.io.FileReader;
  import java.io.FileWriter;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.Set;
  import java.util.StringTokenizer;
  import java.util.TreeSet;
  
  public class CharmedByTheGame {
      
      public static void main(String[] args) {
          
          FastReader in = new FastReader();
          StringBuffer sb = new StringBuffer();
  
          int t = in.nextInt();
  
          while (t > 0) {
  
              int a = in.nextInt(), b = in.nextInt(), n = a + b;
              Set<Integer> breaks = new TreeSet<Integer>();
  
              int p = 0, q = 0;
  
              if (n % 2 == 0) {
  
                  p = n / 2;
                  q = n / 2;
  
              } else {
  
                  p = (n / 2) + 1;
                  q = n / 2;
  
              }
              
              for (int x = 0; x <= p; x++) {
  
                  int y = a - (p - x);
  
                  if (0 <= y && y <= q) {
  
                      breaks.add(x + y);
  
                  }
  
              }
  
              if (n % 2 == 1) {
  
                  p = (n / 2);
                  q = (n / 2) + 1;
  
                  for (int x = 0; x <= p; x++) {
  
                      int y = a - (p - x);
      
                      if (0 <= y && y <= q) {
      
                          breaks.add(x + y);
      
                      }
      
                  }
  
              }
  
              sb.append(breaks.size() + "\n");
  
              for (int z : breaks) {
  
                  sb.append(z + " ");
                  
              }
  
              sb.append("\n");
  
              t--;
              
          }
  
          in.print(sb);
          in.close();
  
      }
  
      static int gcd (int a, int b) {
          
          if (b == 0) {
  
              return a;
  
          } else {
  
              return gcd(b, a % b);
  
          }
  
      }
   
      static long gcd (long a, long b) {
          
          if (b == 0) {
  
              return a;
  
          } else {
  
              return gcd(b, a % b);
  
          }
  
      }
   
      static long lcm (int a, int b) {
  
          return (long) a / gcd(a, b) * b;
  
      }
   
      static long lcm (long a, long b) {
  
          return a / gcd(a, b) * b;
  
      }
  
      public static int search (int l, int r, int[] a, int key) {
  
          while (l <= r) {
  
              int middle = ((r - l) / 2) + l;
  
              if (a[middle] == key) {
  
                  return middle;
  
              } else if (a[middle] < key) {
  
                  l = middle + 1;
  
              } else {
  
                  r = middle - 1;
  
              }
  
          }
  
          return -1;
  
      }
  
      public static void sort (int[] a) {
  
  		ArrayList<Integer> l=new ArrayList<>();
  		for (int i:a) l.add(i);
  		Collections.sort(l);
  		for (int i=0; i<a.length; i++) a[i]=l.get(i);
          
  	}
  
      public static void sort (long[] a) {
  
  		ArrayList<Long> l=new ArrayList<>();
  		for (long i:a) l.add(i);
  		Collections.sort(l);
  		for (int i=0; i<a.length; i++) a[i]=l.get(i);
  
  	}
  
      static class FastReader extends PrintWriter {
  
          BufferedReader br;
          StringTokenizer st;
  
          public FastReader() {
  
              this(System.in, System.out); 
              
          }
  
  		public FastReader(InputStream i, OutputStream o) {
  
  			super(o);
  			br = new BufferedReader(new InputStreamReader(i));
  
  		}
  
          public FastReader(String problemName) throws IOException {
  
  			super(new FileWriter(problemName + ".out"));
  			br = new BufferedReader(new FileReader(problemName + ".in"));
  
  		}
  
          public String next() {
  
              while (st == null || !st.hasMoreElements()) {
  
                  try {
  
                      st = new StringTokenizer(br.readLine());
  
                  } catch (IOException e) {
  
                      e.printStackTrace();
  
                  }
  
              }
  
              return st.nextToken();
  
          }
  
          public int nextInt() {
  
              return Integer.parseInt(next());
  
          }
  
          public long nextLong() {
  
              return Long.parseLong(next());
  
          }
  
          public double nextDouble() {
  
              return Double.parseDouble(next());
  
          }
  
          public String nextLine() {
  
              String str = "";
  
              try {
  
                  str = br.readLine();
  
              } catch (IOException e) {
  
                  e.printStackTrace();
  
              }
  
              return str;
  
          }
  
          public int[] readArray(int n) {
  
  			int[] a = new int[n];
  
  			for (int i = 0; i < n; i++) {
                  
                  a[i] = nextInt();
  			
              }
  
              return a;
  
  		}
  
          public long[] readArrayLong(long n) {
  
  			long[] a = new long[(int) n];
  
  			for (int i = 0; i < n; i++) {
                  
                  a[i] = nextLong();
  			
              }
  
              return a;
  
  		}
  
      }
  
  }
  