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: /*
                         _oo0oo_
                        o8888888o
                        88" . "88
                        (| -_- |)
                        0\  =  /0
                      ___/`---'\___
                    .' \\|     |// '.
                   / \\|||  :  |||// \
                  / _||||| -:- |||||- \
                 |   | \\\  -  /// |   |
                 | \_|  ''\---/''  |_/ |
                 \  .-\__  '-'  ___/-. /
               ___'. .'  /--.--\  `. .'___
            ."" '<  `.___\_<|>_/___.' >' "".
           | | :  `- \`.;`\ _ /`;.`/ - ` : | |
           \  \ `_.   \_ __\ /__ _/   .-` /  /
       =====`-.____`.___ \_____/___.-`___.-'=====
                         `=---='
   
  */
  import java.util.function.Consumer;
  import java.util.*;
  import java.math.*;
  import java.io.*;
  import java.lang.Math.*;
  
  public class KickStart2020 {
  	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());
  		}
  
  		float nextFloat() {
  			return Float.parseFloat(next());
  		}
  
  		String nextLine() {
  			String str = "";
  			try {
  				str = br.readLine();
  			} catch (IOException e) {
  				e.printStackTrace();
  			}
  			return str;
  		}
  	}
  
  	static long gcd(long a, long b) {
  		if (b == 0)
  			return a;
  		return gcd(b, a % b);
  
  	}
  
  	public static class Pair implements Comparable<Pair> {
  		public int index;
  		public int value;
  
  		public Pair(int index, int value) {
  			this.index = index;
  			this.value = value;
  		}
  
  		@Override
  		public int compareTo(Pair other) {
  			// multiplied to -1 as the author need descending sort order
  			return -1 * Integer.valueOf(this.value).compareTo(other.value);
  		}
  	}
  
  	static boolean isPrime(long d) {
  		if (d == 1)
  			return true;
  		for (int i = 2; i <= (long) Math.sqrt(d); i++) {
  			if (d % i == 0)
  				return false;
  		}
  		return true;
  	}
  
  	static void decimalTob(long n, int b, int arr[], int i) {
  		long z = n % b;
  		arr[i] += (int)z;
  		n /= b;
  		if (n > 0) {
  			i++;
  			 decimalTob(n, b,arr, i);
  		}
  	}
  
  	static long powermod(long x, long y, long mod) {
  		long ans = 1;
  		x = x % mod;
  		if (x == 0)
  			return 0;
  		int i = 1;
  		while (y > 0) {
  			if ((y & 1) != 0)
  				ans = (ans * x) % mod;
  			y = y >> 1;
  			x = (x * x) % mod;
  		}
  		return ans;
  	}
  	static boolean isSorted(int arr[]) {
  		for(int i = 1; i <= arr.length; i++) if(arr[i -1] != i) return false;
  		return true;
  	}
  	public static void main(String[] args) throws Exception {
  		FastReader sc = new FastReader();
  		PrintWriter out = new PrintWriter(System.out);
  		int t = sc.nextInt();
  		outerloop:
  			while(t-- > 0) {
                 int n = sc.nextInt();
                 int m = sc.nextInt();
                 int diff = Math.abs(m - n);
                 int z = Math.min(n, m);
                 TreeSet<Integer> ss = new TreeSet<Integer>();
                 int a = diff / 2;
                 int b = (diff + 1) / 2;
                 for(int i = 0; i <= z; i++) {
              	   ss.add(a + i * 2);
              	   ss.add(b + i * 2);
                 }
                 out.println(ss.size());
                 for(int e: ss) out.print(e + " ");
                 out.println();
  			}
             out.close();
  	 }
  }