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: from typing import Counter
  import sys
  from collections import defaultdict as dd
  from math import *
   
  def vinp():
      return map(int,input().split())
  def linp():
      return list(map(int,input().split()))
  def sinp():
      return input()
  def inp():
      return int(input())
  def mod(f):
      return f % 1000000007
  def pr(*x):
      print(*x)
  def finp():
      f=open("input.txt","r")
      f=f.read().split("\n")
      return f
  def finp():
      f=open("input.txt","r")
      f=f.read().split("\n")
      return f
  def fout():
      return open("output.txt","w")
  def fpr(f,x):
      f.write(x+"\n")
  def csort(c):
      sorted(c.items(), key=lambda pair: pair[1], reverse=True)
  def indc(l,n):
      c={}
      for i in range(n):
          c[l[i]]=c.get(l[i],[])+[i+1]
      return c
  def XOR(n) :
      if n % 4 == 0 :
          return n
      if n % 4 == 1 :
          return 1
      if n % 4 == 2 :
          return n + 1
      return 0
  if __name__ =="__main__":
      cou=inp()
      for i in range(cou):
          a,b = vinp()
          z = XOR(a-1)
          z = z^b
          if z!=0:
              if z==a:
                  a+=2
              else:
                  a+=1
          pr(a)