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: #Code by Sounak, IIESTS
  #------------------------------warmup----------------------------
  
  import os
  import sys
  import math
  from io import BytesIO, IOBase
  import io
  from fractions import Fraction
  import collections
  from itertools import permutations
  from collections import defaultdict
  from collections import deque
  from collections import Counter
  import threading
  
  #sys.setrecursionlimit(300000)
  #threading.stack_size(10**8)
  
  BUFSIZE = 8192
   
  class FastIO(IOBase):
      newlines = 0
   
      def __init__(self, file):
          self._fd = file.fileno()
          self.buffer = BytesIO()
          self.writable = "x" in file.mode or "r" not in file.mode
          self.write = self.buffer.write if self.writable else None
   
      def read(self):
          while True:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              if not b:
                  break
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines = 0
          return self.buffer.read()
   
      def readline(self):
          while self.newlines == 0:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              self.newlines = b.count(b"\n") + (not b)
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines -= 1
          return self.buffer.readline()
   
      def flush(self):
          if self.writable:
              os.write(self._fd, self.buffer.getvalue())
              self.buffer.truncate(0), self.buffer.seek(0)
   
   
  class IOWrapper(IOBase):
      def __init__(self, file):
          self.buffer = FastIO(file)
          self.flush = self.buffer.flush
          self.writable = self.buffer.writable
          self.write = lambda s: self.buffer.write(s.encode("ascii"))
          self.read = lambda: self.buffer.read().decode("ascii")
          self.readline = lambda: self.buffer.readline().decode("ascii")
   
   
  sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
  input = lambda: sys.stdin.readline().rstrip("\r\n")
  
  #-------------------game starts now-----------------------------------------------------
  #mod = 9223372036854775807  
  class SegmentTree:
      def __init__(self, data, default=0, func=lambda a, b: max(a,b)):
          """initialize the segment tree with data"""
          self._default = default
          self._func = func
          self._len = len(data)
          self._size = _size = 1 << (self._len - 1).bit_length()
   
          self.data = [default] * (2 * _size)
          self.data[_size:_size + self._len] = data
          for i in reversed(range(_size)):
              self.data[i] = func(self.data[i + i], self.data[i + i + 1])
   
      def __delitem__(self, idx):
          self[idx] = self._default
   
      def __getitem__(self, idx):
          return self.data[idx + self._size]
   
      def __setitem__(self, idx, value):
          idx += self._size
          self.data[idx] = value
          idx >>= 1
          while idx:
              self.data[idx] = self._func(self.data[2 * idx], self.data[2 * idx + 1])
              idx >>= 1
   
      def __len__(self):
          return self._len
   
      def query(self, start, stop):
          if start == stop:
              return self.__getitem__(start)
          stop += 1
          start += self._size
          stop += self._size
   
          res = self._default
          while start < stop:
              if start & 1:
                  res = self._func(res, self.data[start])
                  start += 1
              if stop & 1:
                  stop -= 1
                  res = self._func(res, self.data[stop])
              start >>= 1
              stop >>= 1
          return res
   
      def __repr__(self):
          return "SegmentTree({0})".format(self.data)
      
  class SegmentTree1:
      def __init__(self, data, default=0, func=lambda a, b: a+b):
          """initialize the segment tree with data"""
          self._default = default
          self._func = func
          self._len = len(data)
          self._size = _size = 1 << (self._len - 1).bit_length()
   
          self.data = [default] * (2 * _size)
          self.data[_size:_size + self._len] = data
          for i in reversed(range(_size)):
              self.data[i] = func(self.data[i + i], self.data[i + i + 1])
   
      def __delitem__(self, idx):
          self[idx] = self._default
   
      def __getitem__(self, idx):
          return self.data[idx + self._size]
   
      def __setitem__(self, idx, value):
          idx += self._size
          self.data[idx] = value
          idx >>= 1
          while idx:
              self.data[idx] = self._func(self.data[2 * idx], self.data[2 * idx + 1])
              idx >>= 1
   
      def __len__(self):
          return self._len
   
      def query(self, start, stop):
          if start == stop:
              return self.__getitem__(start)
          stop += 1
          start += self._size
          stop += self._size
   
          res = self._default
          while start < stop:
              if start & 1:
                  res = self._func(res, self.data[start])
                  start += 1
              if stop & 1:
                  stop -= 1
                  res = self._func(res, self.data[stop])
              start >>= 1
              stop >>= 1
          return res
   
      def __repr__(self):
          return "SegmentTree({0})".format(self.data)
      
  MOD=10**9+7
  class Factorial:
      def __init__(self, MOD):
          self.MOD = MOD
          self.factorials = [1, 1]
          self.invModulos = [0, 1]
          self.invFactorial_ = [1, 1]
   
      def calc(self, n):
          if n <= -1:
              print("Invalid argument to calculate n!")
              print("n must be non-negative value. But the argument was " + str(n))
              exit()
          if n < len(self.factorials):
              return self.factorials[n]
          nextArr = [0] * (n + 1 - len(self.factorials))
          initialI = len(self.factorials)
          prev = self.factorials[-1]
          m = self.MOD
          for i in range(initialI, n + 1):
              prev = nextArr[i - initialI] = prev * i % m
          self.factorials += nextArr
          return self.factorials[n]
   
      def inv(self, n):
          if n <= -1:
              print("Invalid argument to calculate n^(-1)")
              print("n must be non-negative value. But the argument was " + str(n))
              exit()
          p = self.MOD
          pi = n % p
          if pi < len(self.invModulos):
              return self.invModulos[pi]
          nextArr = [0] * (n + 1 - len(self.invModulos))
          initialI = len(self.invModulos)
          for i in range(initialI, min(p, n + 1)):
              next = -self.invModulos[p % i] * (p // i) % p
              self.invModulos.append(next)
          return self.invModulos[pi]
   
      def invFactorial(self, n):
          if n <= -1:
              print("Invalid argument to calculate (n^(-1))!")
              print("n must be non-negative value. But the argument was " + str(n))
              exit()
          if n < len(self.invFactorial_):
              return self.invFactorial_[n]
          self.inv(n)  # To make sure already calculated n^-1
          nextArr = [0] * (n + 1 - len(self.invFactorial_))
          initialI = len(self.invFactorial_)
          prev = self.invFactorial_[-1]
          p = self.MOD
          for i in range(initialI, n + 1):
              prev = nextArr[i - initialI] = (prev * self.invModulos[i % p]) % p
          self.invFactorial_ += nextArr
          return self.invFactorial_[n]
   
   
  class Combination:
      def __init__(self, MOD):
          self.MOD = MOD
          self.factorial = Factorial(MOD)
   
      def ncr(self, n, k):
          if k < 0 or n < k:
              return 0
          k = min(k, n - k)
          f = self.factorial
          return f.calc(n) * f.invFactorial(max(n - k, k)) * f.invFactorial(min(k, n - k)) % self.MOD
  mod=10**9+7
  omod=998244353
  #-------------------------------------------------------------------------
  prime = [True for i in range(10001)] 
  prime[0]=prime[1]=False
  #pp=[0]*10000
  def SieveOfEratosthenes(n=10000):
      p = 2
      c=0
      while (p <= n): 
            
          if (prime[p] == True):
              c+=1
              for i in range(p, n+1, p): 
                  #pp[i]=1
                  prime[i] = False
          p += 1
  #-----------------------------------DSU--------------------------------------------------
  class DSU:
      def __init__(self, R, C):
          #R * C is the source, and isn't a grid square
          self.par = range(R*C + 1)
          self.rnk = [0] * (R*C + 1)
          self.sz = [1] * (R*C + 1)
  
      def find(self, x):
          if self.par[x] != x:
              self.par[x] = self.find(self.par[x])
          return self.par[x]
  
      def union(self, x, y):
          xr, yr = self.find(x), self.find(y)
          if xr == yr: return
          if self.rnk[xr] < self.rnk[yr]:
              xr, yr = yr, xr
          if self.rnk[xr] == self.rnk[yr]:
              self.rnk[xr] += 1
  
          self.par[yr] = xr
          self.sz[xr] += self.sz[yr]
  
      def size(self, x):
          return self.sz[self.find(x)]
  
      def top(self):
          # Size of component at ephemeral "source" node at index R*C,
          # minus 1 to not count the source itself in the size
          return self.size(len(self.sz) - 1) - 1
  #---------------------------------Lazy Segment Tree--------------------------------------
  # https://github.com/atcoder/ac-library/blob/master/atcoder/lazysegtree.hpp
  class LazySegTree:
      def __init__(self, _op, _e, _mapping, _composition, _id, v):
          def set(p, x):
              assert 0 <= p < _n
              p += _size
              for i in range(_log, 0, -1):
                  _push(p >> i)
              _d[p] = x
              for i in range(1, _log + 1):
                  _update(p >> i)
   
          def get(p):
              assert 0 <= p < _n
              p += _size
              for i in range(_log, 0, -1):
                  _push(p >> i)
              return _d[p]
   
          def prod(l, r):
              assert 0 <= l <= r <= _n
   
              if l == r:
                  return _e
   
              l += _size
              r += _size
   
              for i in range(_log, 0, -1):
                  if ((l >> i) << i) != l:
                      _push(l >> i)
                  if ((r >> i) << i) != r:
                      _push(r >> i)
   
              sml = _e
              smr = _e
              while l < r:
                  if l & 1:
                      sml = _op(sml, _d[l])
                      l += 1
                  if r & 1:
                      r -= 1
                      smr = _op(_d[r], smr)
                  l >>= 1
                  r >>= 1
   
              return _op(sml, smr)
   
          def apply(l, r, f):
              assert 0 <= l <= r <= _n
              if l == r:
                  return
   
              l += _size
              r += _size
   
              for i in range(_log, 0, -1):
                  if ((l >> i) << i) != l:
                      _push(l >> i)
                  if ((r >> i) << i) != r:
                      _push((r - 1) >> i)
   
              l2 = l
              r2 = r
              while l < r:
                  if l & 1:
                      _all_apply(l, f)
                      l += 1
                  if r & 1:
                      r -= 1
                      _all_apply(r, f)
                  l >>= 1
                  r >>= 1
              l = l2
              r = r2
   
              for i in range(1, _log + 1):
                  if ((l >> i) << i) != l:
                      _update(l >> i)
                  if ((r >> i) << i) != r:
                      _update((r - 1) >> i)
   
          def _update(k):
              _d[k] = _op(_d[2 * k], _d[2 * k + 1])
   
          def _all_apply(k, f):
              _d[k] = _mapping(f, _d[k])
              if k < _size:
                  _lz[k] = _composition(f, _lz[k])
   
          def _push(k):
              _all_apply(2 * k, _lz[k])
              _all_apply(2 * k + 1, _lz[k])
              _lz[k] = _id
   
          _n = len(v)
          _log = _n.bit_length()
          _size = 1 << _log
          _d = [_e] * (2 * _size)
          _lz = [_id] * _size
          for i in range(_n):
              _d[_size + i] = v[i]
          for i in range(_size - 1, 0, -1):
              _update(i)
   
          self.set = set
          self.get = get
          self.prod = prod
          self.apply = apply
   
   
  MIL = 1 << 20
   
   
  def makeNode(total, count):
      # Pack a pair into a float
      return (total * MIL) + count
   
   
  def getTotal(node):
      return math.floor(node / MIL)
   
   
  def getCount(node):
      return node - getTotal(node) * MIL
   
   
  nodeIdentity = makeNode(0.0, 0.0)
   
   
  def nodeOp(node1, node2):
      return node1 + node2
      # Equivalent to the following:
      return makeNode(
          getTotal(node1) + getTotal(node2), getCount(node1) + getCount(node2)
      )
   
   
  identityMapping = -1
   
   
  def mapping(tag, node):
      if tag == identityMapping:
          return node
      # If assigned, new total is the number assigned times count
      count = getCount(node)
      return makeNode(tag * count, count)
   
   
  def composition(mapping1, mapping2):
      # If assigned multiple times, take first non-identity assignment
      return mapping1 if mapping1 != identityMapping else mapping2
  
  class LazySegUpdate():
      def __init__(self, N):
          self.N = N
          n = 4 * N
          self.tree = [0] * n
          self.lazy = [0] * n
          
      def queryHelper(self, index, s, e, l, r):
          if self.lazy[index]:
              # Apply lazy to node.
              update = self.lazy[index]
              self.lazy[index] = 0
              self.tree[index] = max(self.tree[index], update)
              # Check if this is leaf.
              if s != e:
                  self.lazy[2 * index] = max(self.lazy[2 * index], update)
                  self.lazy[2 * index + 1] = max(self.lazy[2 * index + 1], update)
                  
          if s > e or s > r or e < l:
              return 0
          if s >= l and e <= r:
              return self.tree[index]
          # Overlapped.
          mid = (s + e) // 2
          return max(self.queryHelper(2 * index, s, mid, l, r), self.queryHelper(2 * index + 1, mid + 1, e, l, r))
      
      def updateHelper(self, index, s, e, l, r, h):
          if self.lazy[index]:
              # Apply lazy to node.
              update = self.lazy[index]
              self.lazy[index] = 0
              self.tree[index] = max(self.tree[index], update)
              
              if s != e:
                  self.lazy[2 * index] = max(self.lazy[2 * index], update)
                  self.lazy[2 * index + 1] = max(self.lazy[2 * index + 1], update)
                  
          if s > e or s > r or e < l:
              return
          if s >= l and e <= r:
              self.tree[index] = max(self.tree[index], h)
              if s != e:
                  self.lazy[2 * index] = max(self.lazy[2 * index], h)
                  self.lazy[2 * index + 1] = max(self.lazy[2 * index + 1], h)
              return
          
          mid = (s + e) // 2
          self.updateHelper(2 * index, s, mid, l, r, h)
          self.updateHelper(2 * index + 1, mid + 1, e, l, r, h)
          self.tree[index] = max(self.tree[2 * index], self.tree[2 * index + 1])
          
      def query(self, l, r):
          return self.queryHelper(1, 0, self.N - 1, l, r - 1)
      
      def update(self, l, r, h):
          self.updateHelper(1, 0, self.N - 1, l, r - 1, h)
  #---------------------------------Pollard rho--------------------------------------------
  def memodict(f):
      """memoization decorator for a function taking a single argument"""
      class memodict(dict):
          def __missing__(self, key):
              ret = self[key] = f(key)
              return ret
   
      return memodict().__getitem__
   
   
  def pollard_rho(n):
      """returns a random factor of n"""
      if n & 1 == 0:
          return 2
      if n % 3 == 0:
          return 3
   
      s = ((n - 1) & (1 - n)).bit_length() - 1
      d = n >> s
      for a in [2, 325, 9375, 28178, 450775, 9780504, 1795265022]:
          p = pow(a, d, n)
          if p == 1 or p == n - 1 or a % n == 0:
              continue
          for _ in range(s):
              prev = p
              p = (p * p) % n
              if p == 1:
                  return math.gcd(prev - 1, n)
              if p == n - 1:
                  break
          else:
              for i in range(2, n):
                  x, y = i, (i * i + 1) % n
                  f = math.gcd(abs(x - y), n)
                  while f == 1:
                      x, y = (x * x + 1) % n, (y * y + 1) % n
                      y = (y * y + 1) % n
                      f = math.gcd(abs(x - y), n)
                  if f != n:
                      return f
      return n
   
   
  @memodict
  def prime_factors(n):
      """returns a Counter of the prime factorization of n"""
      if n <= 1:
          return Counter()
      f = pollard_rho(n)
      return Counter([n]) if f == n else prime_factors(f) + prime_factors(n // f)
   
   
  def distinct_factors(n):
      """returns a list of all distinct factors of n"""
      factors = [1]
      for p, exp in prime_factors(n).items():
          factors += [p**i * factor for factor in factors for i in range(1, exp + 1)]
      return factors
   
   
  def all_factors(n):
      """returns a sorted list of all distinct factors of n"""
      small, large = [], []
      for i in range(1, int(n**0.5) + 1, 2 if n & 1 else 1):
          if not n % i:
              small.append(i)
              large.append(n // i)
      if small[-1] == large[-1]:
          large.pop()
      large.reverse()
      small.extend(large)
      return small
  #-----------------------------------Sorted List------------------------------------------
  class SortedList:
      def __init__(self, iterable=[], _load=200):
          """Initialize sorted list instance."""
          values = sorted(iterable)
          self._len = _len = len(values)
          self._load = _load
          self._lists = _lists = [values[i:i + _load] for i in range(0, _len, _load)]
          self._list_lens = [len(_list) for _list in _lists]
          self._mins = [_list[0] for _list in _lists]
          self._fen_tree = []
          self._rebuild = True
   
      def _fen_build(self):
          """Build a fenwick tree instance."""
          self._fen_tree[:] = self._list_lens
          _fen_tree = self._fen_tree
          for i in range(len(_fen_tree)):
              if i | i + 1 < len(_fen_tree):
                  _fen_tree[i | i + 1] += _fen_tree[i]
          self._rebuild = False
   
      def _fen_update(self, index, value):
          """Update `fen_tree[index] += value`."""
          if not self._rebuild:
              _fen_tree = self._fen_tree
              while index < len(_fen_tree):
                  _fen_tree[index] += value
                  index |= index + 1
   
      def _fen_query(self, end):
          """Return `sum(_fen_tree[:end])`."""
          if self._rebuild:
              self._fen_build()
   
          _fen_tree = self._fen_tree
          x = 0
          while end:
              x += _fen_tree[end - 1]
              end &= end - 1
          return x
   
      def _fen_findkth(self, k):
          """Return a pair of (the largest `idx` such that `sum(_fen_tree[:idx]) <= k`, `k - sum(_fen_tree[:idx])`)."""
          _list_lens = self._list_lens
          if k < _list_lens[0]:
              return 0, k
          if k >= self._len - _list_lens[-1]:
              return len(_list_lens) - 1, k + _list_lens[-1] - self._len
          if self._rebuild:
              self._fen_build()
   
          _fen_tree = self._fen_tree
          idx = -1
          for d in reversed(range(len(_fen_tree).bit_length())):
              right_idx = idx + (1 << d)
              if right_idx < len(_fen_tree) and k >= _fen_tree[right_idx]:
                  idx = right_idx
                  k -= _fen_tree[idx]
          return idx + 1, k
   
      def _delete(self, pos, idx):
          """Delete value at the given `(pos, idx)`."""
          _lists = self._lists
          _mins = self._mins
          _list_lens = self._list_lens
   
          self._len -= 1
          self._fen_update(pos, -1)
          del _lists[pos][idx]
          _list_lens[pos] -= 1
   
          if _list_lens[pos]:
              _mins[pos] = _lists[pos][0]
          else:
              del _lists[pos]
              del _list_lens[pos]
              del _mins[pos]
              self._rebuild = True
   
      def _loc_left(self, value):
          """Return an index pair that corresponds to the first position of `value` in the sorted list."""
          if not self._len:
              return 0, 0
   
          _lists = self._lists
          _mins = self._mins
   
          lo, pos = -1, len(_lists) - 1
          while lo + 1 < pos:
              mi = (lo + pos) >> 1
              if value <= _mins[mi]:
                  pos = mi
              else:
                  lo = mi
   
          if pos and value <= _lists[pos - 1][-1]:
              pos -= 1
   
          _list = _lists[pos]
          lo, idx = -1, len(_list)
          while lo + 1 < idx:
              mi = (lo + idx) >> 1
              if value <= _list[mi]:
                  idx = mi
              else:
                  lo = mi
   
          return pos, idx
   
      def _loc_right(self, value):
          """Return an index pair that corresponds to the last position of `value` in the sorted list."""
          if not self._len:
              return 0, 0
   
          _lists = self._lists
          _mins = self._mins
   
          pos, hi = 0, len(_lists)
          while pos + 1 < hi:
              mi = (pos + hi) >> 1
              if value < _mins[mi]:
                  hi = mi
              else:
                  pos = mi
   
          _list = _lists[pos]
          lo, idx = -1, len(_list)
          while lo + 1 < idx:
              mi = (lo + idx) >> 1
              if value < _list[mi]:
                  idx = mi
              else:
                  lo = mi
   
          return pos, idx
   
      def add(self, value):
          """Add `value` to sorted list."""
          _load = self._load
          _lists = self._lists
          _mins = self._mins
          _list_lens = self._list_lens
   
          self._len += 1
          if _lists:
              pos, idx = self._loc_right(value)
              self._fen_update(pos, 1)
              _list = _lists[pos]
              _list.insert(idx, value)
              _list_lens[pos] += 1
              _mins[pos] = _list[0]
              if _load + _load < len(_list):
                  _lists.insert(pos + 1, _list[_load:])
                  _list_lens.insert(pos + 1, len(_list) - _load)
                  _mins.insert(pos + 1, _list[_load])
                  _list_lens[pos] = _load
                  del _list[_load:]
                  self._rebuild = True
          else:
              _lists.append([value])
              _mins.append(value)
              _list_lens.append(1)
              self._rebuild = True
   
      def discard(self, value):
          """Remove `value` from sorted list if it is a member."""
          _lists = self._lists
          if _lists:
              pos, idx = self._loc_right(value)
              if idx and _lists[pos][idx - 1] == value:
                  self._delete(pos, idx - 1)
   
      def remove(self, value):
          """Remove `value` from sorted list; `value` must be a member."""
          _len = self._len
          self.discard(value)
          if _len == self._len:
              raise ValueError('{0!r} not in list'.format(value))
   
      def pop(self, index=-1):
          """Remove and return value at `index` in sorted list."""
          pos, idx = self._fen_findkth(self._len + index if index < 0 else index)
          value = self._lists[pos][idx]
          self._delete(pos, idx)
          return value
   
      def bisect_left(self, value):
          """Return the first index to insert `value` in the sorted list."""
          pos, idx = self._loc_left(value)
          return self._fen_query(pos) + idx
   
      def bisect_right(self, value):
          """Return the last index to insert `value` in the sorted list."""
          pos, idx = self._loc_right(value)
          return self._fen_query(pos) + idx
   
      def count(self, value):
          """Return number of occurrences of `value` in the sorted list."""
          return self.bisect_right(value) - self.bisect_left(value)
   
      def __len__(self):
          """Return the size of the sorted list."""
          return self._len
   
      def __getitem__(self, index):
          """Lookup value at `index` in sorted list."""
          pos, idx = self._fen_findkth(self._len + index if index < 0 else index)
          return self._lists[pos][idx]
   
      def __delitem__(self, index):
          """Remove value at `index` from sorted list."""
          pos, idx = self._fen_findkth(self._len + index if index < 0 else index)
          self._delete(pos, idx)
   
      def __contains__(self, value):
          """Return true if `value` is an element of the sorted list."""
          _lists = self._lists
          if _lists:
              pos, idx = self._loc_left(value)
              return idx < len(_lists[pos]) and _lists[pos][idx] == value
          return False
   
      def __iter__(self):
          """Return an iterator over the sorted list."""
          return (value for _list in self._lists for value in _list)
   
      def __reversed__(self):
          """Return a reverse iterator over the sorted list."""
          return (value for _list in reversed(self._lists) for value in reversed(_list))
   
      def __repr__(self):
          """Return string representation of sorted list."""
          return 'SortedList({0})'.format(list(self))
  #---------------------------------Binary Search------------------------------------------
  def binarySearch(arr, n, key):
      left = 0
      right = n-1
      mid = 0
      res = n
      while (left <= right):
          mid = (right + left)//2
          if (arr[mid] > key):
              res=mid
              right = mid-1
          else:
              left = mid + 1
      return res
  
  def binarySearch1(arr, n, key):
      left = 0
      right = n-1
      mid = 0
      res=-1
      while (left <= right):
          mid = (right + left)//2
          if (arr[mid] > key):
              right = mid-1
          else:
              res=mid
              left = mid + 1
      return res
  #---------------------------------running code------------------------------------------
  t=1
  t=int(input())
  for _ in range (t):
      #n=int(input())
      a,b=map(int,input().split())
      #a=list(map(int,input().split()))
      #b=list(map(int,input().split()))
      #s=input()
      #n=len(s)
      xor=0
      if a>1:
          d=(a-1)%4
          if d==0:
              xor=a-1
          elif d==1:
              xor=1
          elif d==2:
              xor=a
      if xor==b:
          print(a)
      elif xor^b==a:
          print(a+2)
      else:
          print(a+1)