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.util.*;
  import java.util.function.Function;
  import java.util.stream.Collectors;
  
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.*;
  import java.math.*;
  
  
  public class Solution
  {
  	static StringBuilder sb;
  	static dsu dsu;
  	static long fact[];
  	static long mod=(long)(1e9+7);
  	static ArrayList<Integer>prime;
  	static long A[],dp[];
  	static int n;
  	static ArrayList<Integer>adj[];
  	static int num[];
  	static ArrayList<String>pre;
  	
  	static void solve()
      {
  		int a=i();
  		int b=i();
  		
  		int n=a+b;
  		TreeSet<Integer>ts=new TreeSet<>();
  		
  		// a sevve first
  		
  		int na=(n+1)/2;
  		int nb=n-na;
  		
  		int min=Math.abs(na-a);
  		ts.add(min);
  		for(int k=0;k<Math.min(a, b);k++)
  		{
  			ts.add((k+1)*2+min);
  		}
  		//System.out.println(ts);
  		// if b servers
  		
  		nb=(n+1)/2;
  		na=n-nb;
  		min=Math.abs(nb-b);
  		ts.add(min);
  		for(int k=0;k<Math.min(a, b);k++)
  		{
  			ts.add((k+1)*2+min);
  		}
  		
  		//System.out.println(ts);
  		sb.append(ts.size()+"\n");
  		for(int aa:ts)
  			sb.append(aa+" ");
  		sb.append("\n");
  		//System.out.println(ts);
  		
  		
  		
  		
  		
  		
  		
  		
  		
      }
  	public static void main(String[] args)
  	 {
  		 sb=new StringBuilder();
  		 pre=new ArrayList<>();
  		
  		 
  		 
  	     int test=i();
  	    for(int tt=1;tt<=test;tt++) 
  	    {
  	         solve();
  	    }
  	    System.out.println(sb);
  	 }
  	 
  //*******************************************NCR%P*******************************************************	 
  	 static long ncr(int n, int r)
  	 {
  		 if(r>n)
  			 return (long)0;
  		 
  		 long res=fact[n]%mod;
  		 //System.out.println(res);
  		 res=((long)(res%mod)*(long)(p(fact[r],mod-2)%mod))%mod;
  		 res=((long)(res%mod)*(long)(p(fact[n-r],mod-2)%mod))%mod;
  		 //System.out.println(res);
  		 return res;
  		
  		 
  	 }
  		static long p(long x, long y)//POWER FXN //
  		{
  			if(y==0)
  				return 1;
  			
  			long res=1;
  			while(y>0)
  			{
  				if(y%2==1)
  				{
  					res=(res*x)%mod;
  					y--;
  				}
  				
  				x=(x*x)%mod;
  				y=y/2;
  				
  				
  			}
  			return res;
  		}
  		static long ceil(long num, long den)
  		{
  			return (long)(num+den-1)/den;
  		}
  		
  
  //*******************************************END*******************************************************
  		static int LowerBound(long a[], long x, int i, int j) 
  		{ 
  			//X is the key value
  			int l=i;int r=j;
  			int lb=-1;
  			  while(l<=r)
  			  {
  			    int m=(l+r)/2;
  			    
  			    if(a[m]>=x) 
  			    {
  			    	lb=m;
  			    	r=m-1;
  			    }
  			    else l=m+1;
  			  }
  			  return lb;
  		}
  		static int UpperBound(long a[], long x, int i, int j) 
  		{// x is the key or target value
  		    int l=i,r=j;
  		    int ans=-1;
  		    while(l<=r)
  		    {
  		       int m=(l+r)/2;
  		       
  		       if(a[m]<=x) 
  		       {
  		    	   ans=m;
  		    	   l=m+1;
  		       }
  		       else r=m-1;
  		    }
  		    return ans;
  		 }
  		
  		
  		
  	 
  	 
  	 //*********************************Disjoint set union*************************//
  	 static class dsu
  	 {
  		 int parent[];
  		 dsu(int n)
  		 {
  			 parent=new int[n+1];
  			 for(int i=0;i<=n;i++)
  				 parent[i]=-1;
  		 }
  		 int find(int a)
  		 {
  			 if(parent[a]<0)
  				 return a;
  			 else
  			 {
  				 int x=find(parent[a]);
  				 parent[a]=x;
  				 return x;
  			 }
  		 }
  		 void merge(int a,int b)
  		 {
  			 a=find(a);
  			 b=find(b);
  			 if(a==b)
  				 return;
  			 parent[b]=a;
  		 }
  	 }
  	 
  	 
  	 
  //*******************************************PRIME FACTORIZE *****************************************************************************************************//
  	 static TreeMap<Integer,Integer> prime(long n)
  	 {
  		 TreeMap<Integer,Integer>h=new TreeMap<>();
  		 long num=n;
  		 for(int i=2;i<=Math.sqrt(num);i++)
  		 {
  			 if(n%i==0)
  			 {
  				 int nt=0;
  				 while(n%i==0) {
  					 n=n/i;
  					 nt++;
  				 }
  				 h.put(i, nt);
  			 }
  		 }
  		 if(n!=1)
  			 h.put((int)n, 1);
  		 return h;
  		 
  	 }
  	 
  	
  	
  //*************CLASS PAIR ***********************************************************************************************************************************************
  	   
  	 
  	 static class pair implements Comparable<pair>
  	    {
  	        int x;
  	        int  y;
  	       
  	        pair(int x, int y) {
  	            this.x = x;
  	            this.y = y;
  	          
  	        }
  	        public int compareTo(pair o)
  	        {
  	        	return(int) (y-o.y);
  	        	
  	        }
  	        public int hashCode() 
  	        { 
  	                final int temp = 14; 
  	                int ans = 1; 
  	                ans =x*31+y*13; 
  	                return (int)ans;
  	        }
  	        @Override
  	         public boolean equals(Object o) 
  	         { 
  	             if (this == o) { 
  	                 return true; 
  	             } 
  	             if (o == null) { 
  	                 return false; 
  	             } 
  	             if (this.getClass() != o.getClass()) { 
  	                 return false; 
  	             } 
  	             pair other = (pair)o; 
  	             if (this.x != other.x || this.y!=other.y) { 
  	                 return false; 
  	             } 
  	             return true; 
  	         }
  	    } 
  	        
  	        
  			
  //*************CLASS PAIR *****************************************************************************************************************************************************
  	
  	
  	
  
      static class InputReader {
          private InputStream stream;
          private byte[] buf = new byte[1024];
          private int curChar;
          private int numChars;
          private SpaceCharFilter filter;
  
          public InputReader(InputStream stream) {
              this.stream = stream;
          }
  
          public int read() {
              if (numChars == -1)
                  throw new InputMismatchException();
              if (curChar >= numChars) {
                  curChar = 0;
                  try {
                      numChars = stream.read(buf);
                  } catch (IOException e) {
                      throw new InputMismatchException();
                  }
                  if (numChars <= 0)
                      return -1;
              }
              return buf[curChar++];
          }
  
          public int Int() {
              int c = read();
              while (isSpaceChar(c))
                  c = read();
              int sgn = 1;
              if (c == '-') {
                  sgn = -1;
                  c = read();
              }
              int res = 0;
              do {
                  if (c < '0' || c > '9')
                      throw new InputMismatchException();
                  res *= 10;
                  res += c - '0';
                  c = read();
              } while (!isSpaceChar(c));
              return res * sgn;
          }
  
          public String String() {
              int c = read();
              while (isSpaceChar(c))
                  c = read();
              StringBuilder res = new StringBuilder();
              do {
                  res.appendCodePoint(c);
                  c = read();
              } while (!isSpaceChar(c));
              return res.toString();
          }
  
          public boolean isSpaceChar(int c) {
              if (filter != null)
                  return filter.isSpaceChar(c);
              return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
          }
  
          public String next() {
              return String();
          }
  
          public interface SpaceCharFilter {
              public boolean isSpaceChar(int ch);
          }
      }
  
      static class OutputWriter {
          private final PrintWriter writer;
  
          public OutputWriter(OutputStream outputStream) {
              writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
          }
  
          public OutputWriter(Writer writer) {
              this.writer = new PrintWriter(writer);
          }
  
          public void print(Object... objects) {
              for (int i = 0; i < objects.length; i++) {
                  if (i != 0)
                      writer.print(' ');
                  writer.print(objects[i]);
              }
          }
  
          public void printLine(Object... objects) {
              print(objects);
              writer.println();
          }
  
          public void close() {
              writer.close();
          }
  
          public void flush() {
              writer.flush();
          }
      }
  
      static InputReader in = new InputReader(System.in);
      static OutputWriter out = new OutputWriter(System.out);
     
  
      public static int[] sort(int[] a) {
          int n = a.length;
          ArrayList<Integer> l = new ArrayList<>();
          for (int i : a)
              l.add(i);
          Collections.sort(l);
          for (int i = 0; i < l.size(); i++)
              a[i] = l.get(i);
          return a;
      }
      public static long[] sort(long[] a) {
          int n = a.length;
          ArrayList<Long> l = new ArrayList<>();
          for (long i : a)
              l.add(i);
          Collections.sort(l);
          for (int i = 0; i < l.size(); i++)
              a[i] = l.get(i);
          return a;
      }
  
      public static long pow(long x, long y) {
          long res = 1;
          while (y > 0) {
              if (y % 2 != 0) {
                  res = (res * x);// % modulus;
                  y--;
  
              }
              x = (x * x);// % modulus;
              y = y / 2;
          }
          return res;
      }
  //GCD___+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
      public static long gcd(long x, long y) {
          if (x == 0)
              return y%mod;
          else
              return gcd(y % x, x);
      }
      //****************LOWEST COMMON MULTIPLE   *************************************************************************************************************************************
  
      public static long lcm(long x, long y) {
          return (x * (y / gcd(x, y)));
      }
  //INPUT PATTERN******************************************************************************************************************************************************************
      public static int i() {
          return in.Int();
      }
  
      public static long l() {
          String s = in.String();
          return Long.parseLong(s);
      }
  
      public static String s() {
          return in.String();
      }
  
      public static int[] readArray(int n) {
          int A[] = new int[n];
          for (int i = 0; i < n; i++) {
              A[i] = i();
          }
          return A;
      }
  
      public static long[] readArray(long n) {
          long A[] = new long[(int) n];
          for (int i = 0; i < n; i++) {
              A[i] = l();
          }
          return A;
      }
      public int[][] deepCopy(int[][] matrix) {
  		return java.util.Arrays.stream(matrix).map(el -> el.clone()).toArray($ -> matrix.clone());
  		}
   
  
  }
  
  
  
  
  
  
  	