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: /*
      This code is written by KESHAV DAGA
      @keshavkeshu
  */
  
  
  import java.util.*;
  import java.io.*;
  public class Main  
  {
      static FastReader in=new FastReader();
      static final Random random=new Random();
      static int mod=1000000007;
      static int inf=Integer.MAX_VALUE;
      static int ninf=Integer.MIN_VALUE;
      static HashMap<String,Integer>map=new HashMap<>();
      static String yes="YES",no="NO";
  
      public static void main(String args[]) throws IOException {
          /*
              This is main section or the coding part
              @keshavkeshu
          */
          int t=in.nextInt();
          StringBuilder res=new StringBuilder();
          while(t-->0)
          {
              // logic
              int n=in.nextInt(),m=in.nextInt();
              ArrayList<Integer> ans =compute(n,m);
              int size=ans.size();
              res.append(size+"\n");
              for(int i=0;i<size;i++)
              {
                  res.append(ans.get(i)+" ");
              }
              res.append("\n");
          }
          
          print(res);
      }
      
      public static ArrayList<Integer> compute(int a, int b) {
  		int n = a + b;
  		ArrayList<Integer> al = new ArrayList<>();
  		if (n % 2 == 0) {
  			for (int i = Math.max(a, b) - n / 2; i <= Math.min(a, b) +  n / 2; i+=2) {
  				al.add(i);
  			}
  		} else {
  			for (int i = Math.max(a, b) - n / 2 - 1; i <= Math.min(a, b) +  n / 2 + 1; i+=2) {
  				al.add(i);
  				al.add(i + 1);
  			}
  		}
  		return al;
  	}
      
     
      //  2 1 
      // 1 2
     
     
      
      static int max(int a, int b)
      {
          if(a<b)
          	return b;
          return a;
      }
      
      static int min(int a, int b)
      {
          if(a>b)
          	return b;
          return a;
      }
      
      static long max(long a, long b)
      {
          if(a<b)
          	return b;
          return a;
      }
      
      static long min(long a, long b)
      {
          if(a>b)
          	return b;
          return a;
      }
      static int max(int a, int b, int c)
      {
          if(a>b && a>c)
          	return a;
          else if(b>a && b>c)
              return b;
          else
              return c;
      }
      
      static int min(int a, int b, int c)
      {
          if(a<b && a<c)
          	return a;
          else if(b<a && b<c)
              return b;
          else
              return c;
      }
      
       
      static void ruffleSort(int[] a) {
          int n=a.length;
          for (int i=0; i<n; i++) {
              int oi=random.nextInt(n), temp=a[oi];
              a[oi]=a[i]; a[i]=temp;
          }
          Arrays.sort(a);
      }
  
      static < E > void print(E res)
      {
          System.out.println(res);
      }
      
      static < E > void printd(E res)
      {
          System.out.println(res);
      }
  
  
      static  int gcd(int a,int b)
      {
          if(b==0)
          {
              return a;
          }
          return gcd(b,a%b);
      }
      
      static int lcm(int a, int b)
      {
          return (a / gcd(a, b)) * b;
      }
  
      
      static int abs(int a)
      {
          if(a<0)
              return -1*a;
          return a;
      }
  
      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 [] ria(int n) {
              int res [] = new int [n];
              for(int i = 0; i<n; i++)res[i] = nextInt();
              return res;
          }
          long [] rla(int n) {
              long res [] = new long [n];
              for(int i = 0; i<n; i++)res[i] = nextLong();
              return res;
          }
      }
  
  }
  