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 Self;
  
  import java.util.Scanner;
  import java.util.Set;
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.Comparator;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Stack;
  import java.util.StringTokenizer;
  import java.util.TreeMap;
  import java.util.Queue;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  import java.util.PriorityQueue;
  
  public class Solution {
  
  	static FastReader scn = new FastReader();
  
  	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;
  		}
  	}
  
  	static long mod = (long) (1e9 + 7);
  	static int maxN = (int) 2e5 + 10;
  	static StringBuilder sb = new StringBuilder();
  
  	public static void main(String[] args) {
  
  		int t = 1;
  		t = scn.nextInt();
  
  		while (t-- > 0) {
  
  //			int n = scn.nextInt();
  			int a = scn.nextInt();
  			int b = scn.nextInt();
  			int n = a + b;
  			int diff = Math.abs(a - b);
  
  			Set<Integer> s = new HashSet<Integer>();
  
  			for (int k = 0; k <= n / 2; k++) {
  
  				if (n % 2 == 0) {
  
  					int temp;
  
  					if (k % 2 == 0)
  						temp = diff;
  
  					else
  						temp = diff - 2;
  
  					if (temp >= 0 && temp % 4 == 0 && temp / 4 <= k / 2) {
  						s.add(k);
  						s.add(n - k);
  					}
  
  				}
  
  				else {
  
  					if (diff % 2 == 1 && diff <= 2 * k + 1) {
  						s.add(k);
  						s.add(n - k);
  					}
  				}
  			}
  
  			sb.append(s.size() + "\n");
  
  			for (int i = 0; i <= n; i++) {
  
  				if (s.contains(i))
  					sb.append(i + " ");
  
  			}
  
  			sb.append("\n");
  		}
  
  		System.out.println(sb);
  
  	}
  
  	private static boolean isSorted(int[] arr) {
  
  		for (int i = 0; i < arr.length; i++) {
  
  			if (arr[i] != i + 1)
  				return false;
  
  		}
  
  		return true;
  
  	}
  
  	public static void yes() {
  		sb.append("YES\n");
  	}
  
  	public static void no() {
  		sb.append("NO\n");
  	}
  
  	public static void swap(int[] arr, int i, int j) {
  		int temp = arr[i];
  		arr[i] = arr[j];
  		arr[j] = temp;
  	}
  
  	public static long[] longInput(int n) {
  
  		long[] arr = new long[n];
  
  		for (int i = 0; i < n; i++) {
  			arr[i] = scn.nextLong();
  		}
  
  		return arr;
  
  	}
  
  	public static int[] input(int n) {
  
  		int[] arr = new int[n];
  
  		for (int i = 0; i < n; i++) {
  			arr[i] = scn.nextInt();
  		}
  
  		return arr;
  
  	}
  
  }