description: Alice gave Bob two integers a and b (a > 0 and b ≥ 0). Being a curious boy, Bob wrote down an array of non-negative integers with \operatorname{MEX} value of all elements equal to a and \operatorname{XOR} value of all elements equal to b.
  
  What is the shortest possible length of the array Bob wrote?
  
  Recall that the \operatorname{MEX} (Minimum EXcluded) of an array is the minimum non-negative integer that does not belong to the array and the \operatorname{XOR} of an array is the [bitwise XOR](https://en.wikipedia.org/wiki/Bitwise_operation#XOR) of all the elements of the array.
  
  Input
  
  The input consists of multiple test cases. The first line contains an integer t (1 ≤ t ≤ 5 ⋅ 10^4) — the number of test cases. The description of the test cases follows.
  
  The only line of each test case contains two integers a and b (1 ≤ a ≤ 3 ⋅ 10^5; 0 ≤ b ≤ 3 ⋅ 10^5) — the \operatorname{MEX} and \operatorname{XOR} of the array, respectively.
  
  Output
  
  For each test case, output one (positive) integer — the length of the shortest array with \operatorname{MEX} a and \operatorname{XOR} b. We can show that such an array always exists.
  
  Example
  
  Input
  
  
  5
  1 1
  2 1
  2 0
  1 10000
  2 10000
  
  
  Output
  
  
  3
  2
  3
  2
  3
  
  Note
  
  In the first test case, one of the shortest arrays with \operatorname{MEX} 1 and \operatorname{XOR} 1 is [0, 2020, 2021].
  
  In the second test case, one of the shortest arrays with \operatorname{MEX} 2 and \operatorname{XOR} 1 is [0, 1].
  
  It can be shown that these arrays are the shortest arrays possible.
solution: import sys
  try:
  	sys.stdin = open('inputf.in', 'r')
  	sys.stdout=open('outputf.in','w')	
  except:
  	pass
  #------------------------------------------------
  #importing libraries
  import math
  import sys
  from math import sqrt
  from collections import defaultdict
  from collections import Counter
  import string
  from collections import deque
  from functools import cmp_to_key
  import bisect
  from collections import OrderedDict
  import heapq as hq
  from queue import PriorityQueue
  #----------------------------------------------------------------------
  #helper Module
  # sys.setrecursionlimit(1000000)
  MOD=(10**9)+7
  #----------------------------------------------------------------------
  #input snippets
  def ii():return int(sys.stdin.readline().strip())
  def si():return sys.stdin.readline().strip()
  def li():return list(map(int,sys.stdin.readline().strip().split()))
  def lsi():return list(map(str,sys.stdin.readline().strip().split()))
  def mi():return map(int,sys.stdin.readline().strip().split())
  def dparr(m,n): return [[0]*n for i in range(m)]
  #----------------------------------------------------------------------
  def computeXOR(n) :
  	if n % 4 == 0 :
  		return n
  	if n % 4 == 1 :
  		return 1
   
  	if n % 4 == 2 :
  		return n + 1
  	return 0
  t=ii()
  for _ in range(t):
  	a,b=mi()
  	ob=b
  	xv=computeXOR(a-1)	
  	if(xv==b):
  		print(a)
  	else:
  		req=xv^b
  		if(req==a):
  			print(a+2)
  		else:
  			print(a+1)
  
  
  
  
  