Author has gone out of the stories about Vasiliy, so here is just a formal task description.

You are given q queries and a multiset A, initially containing only integer 0. There are three types of queries:

  1. "+ x" — add integer x to multiset A.
  2. "- x" — erase one occurrence of integer x from multiset A. It's guaranteed that at least one x is present in the multiset A before this query.
  3. "? x" — you are given integer x and need to compute the value <image>, i.e. the maximum value of bitwise exclusive OR (also know as XOR) of integer x and some integer y from the multiset A.



Multiset is a set, where equal elements are allowed.

Input

The first line of the input contains a single integer q (1 ≤ q ≤ 200 000) — the number of queries Vasiliy has to perform.

Each of the following q lines of the input contains one of three characters '+', '-' or '?' and an integer xi (1 ≤ xi ≤ 109). It's guaranteed that there is at least one query of the third type.

Note, that the integer 0 will always be present in the set A.

Output

For each query of the type '?' print one integer — the maximum value of bitwise exclusive OR (XOR) of integer xi and some integer from the multiset A.

Example

Input

10
+ 8
+ 9
+ 11
+ 6
+ 1
? 3
- 8
? 3
? 8
? 11


Output

11
10
14
13

Note

After first five operations multiset A contains integers 0, 8, 9, 11, 6 and 1.

The answer for the sixth query is integer <image> — maximum among integers <image>, <image>, <image>, <image> and <image>.

trie = [0, 0, None, None]
answer = [0] * 32

def add(bit=0, node=trie):
	node[ar[bit]] += 1
	if not node[ar[bit] + 2]:
		node[ar[bit] + 2] = [0, 0, None, None]
	if bit != 31:
		add(bit + 1, node[ar[bit] + 2])

def delete(bit=0, node=trie):
	node[ar[bit]] -= 1
	if bit != 31:
		delete(bit+1, node[ar[bit] + 2])
	if not node[ar[bit]]:
		node[ar[bit] + 2] = None


def query(bit=0, node=trie):
	if node[not ar[bit]]:
		answer[bit] = 1
		if bit != 31:
			query(bit+1, node[(not ar[bit]) + 2])

	else:
		answer[bit] = 0
		if bit != 31:
			query(bit+1, node[ar[bit] + 2])

def convert():
	d = 1
	a = 0
	for i in xrange(31, -1, -1):
		a += answer[i] * d
		d <<= 1
	return a

def bits(number):
	ar = [0]*32
	i = 1
	while number:
		ar[32-i] = (number & 1)
		number >>= 1
		i += 1
	return ar

ar = [0]*32
add()
for i in xrange(input()):
	line = raw_input().split()
	ar = bits(int(line[1]))
	if line[0] == '+': add()
	elif line[0] == '-': delete()
	else:
		try:
			query()
			print convert()
		except:
			print line[1]