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 sys,math
  from collections import deque,defaultdict
  import operator as op
  from functools import reduce
  from itertools import permutations
  import heapq
  
  #sys.setrecursionlimit(10**7) 
  # OneDrive\Documents\codeforces
  
  I=sys.stdin.readline
  
  alpha="abcdefghijklmnopqrstuvwxyz"
  
  mod=10**9 + 7
  
  """
  x_move=[-1,0,1,0,-1,1,1,-1]
  y_move=[0,1,0,-1,1,1,-1,-1]
  """
  def ii():
  	return int(I().strip())
  def li():
  	return list(map(int,I().strip().split()))
  def mi():
  	return map(int,I().strip().split())
  
  
  def ncr(n, r):
      r = min(r, n-r)
      numer = reduce(op.mul, range(n, n-r, -1), 1)
      denom = reduce(op.mul, range(1, r+1), 1)
      return numer // denom 
  
  def ispali(s):
  	i=0
  	j=len(s)-1
  
  	while i<j:
  		if s[i]!=s[j]:
  			return False
  		i+=1
  		j-=1
  	return True
  
  
  
  def isPrime(n):
  	if n<=1:
  		return False
  	elif n<=2:
  		return True
  	else:
  		
  		for i in range(2,int(n**.5)+1):
  			if n%i==0:
  				return False
  		return True
  
  
  def main():
  	for _ in range(ii()):
  		a,b=mi()
  
  		ttl=a+b
  		ans=[]
  		if ttl%2:
  			x1,y1=ttl//2,(ttl//2)+1
  			x2,y2=y1,x1
  			dmax1=min(x1,b)+min(y1,a)
  			dmax2=min(x2,b)+min(y2,a)
  			ans.append(dmax1)
  			ans.append(dmax2)
  			dmax1-=2
  			dmax2-=2
  			for i in range(min(a,b)):
  				ans.append(dmax1)
  				ans.append(dmax2)
  				dmax1-=2
  				dmax2-=2
  		else:
  			x,y=ttl//2,ttl//2
  			dmax=min(x,b)+min(y,a)
  			ans.append(dmax)
  			dmax-=2
  			for i in range(min(a,b)):
  				ans.append(dmax)
  				dmax-=2
  		ans.sort()
  		print(len(ans))
  		print(*ans)
  
  
  
  
  
  		
  
  
  
  
  
  		
  	
  			
  
  	
  
  		
  
  	
  
  
  
  
  
  
  
  
  
  
  
  
  
  		
  
  		
  
  
  		
  
  
  
  
  
  
  
  
  
  		
  
  
  
  		
  
  
  
  
  
  
  
  	
  
  	
  
  
  	
  	
  
  	
  
  
  
  
  	
  
  
   
  		
  
  
  
  
  
  	
  
  	
  
  
  			
  
  
  
  
  
  
  
  
  
  	
  
  
  				
  
  
  	
  
  	
  	
  
  	
  
  
  
  
  	
  
  
  	
  
  
  
  
  		
  	
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  					
  
  if __name__ == '__main__':
  	main()