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>.
# Why do we fall ? So we can learn to pick ourselves up.



class Node:
    def __init__(self):
        self.left = None
        self.right = None
        self.cnt = 0

class Trie:
    def __init__(self):
        self.root = Node()

    def insert(self,x):
        self.temp = self.root
        for i in range(31,-1,-1):
            curbit = (x>>i)&1
            if curbit:
                if not self.temp.right:
                    self.temp.right = Node()
                self.temp = self.temp.right
                self.temp.cnt += 1
            else:
                if not self.temp.left:
                    self.temp.left = Node()
                self.temp = self.temp.left
                self.temp.cnt += 1

    def remove(self,x):
        self.temp = self.root
        for i in range(31,-1,-1):
            curbit = (x>>i)&1
            if curbit:
                self.temp = self.temp.right
                self.temp.cnt -= 1
            else:
                self.temp = self.temp.left
                self.temp.cnt -= 1
    def maxxor(self,x):
        self.temp = self.root
        self.ss = 0
        for i in range(31,-1,-1):
            curbit = (x>>i)&1
            if curbit:
                if self.temp.left and self.temp.left.cnt:
                    self.ss += (1<<i)
                    self.temp = self.temp.left
                elif self.temp.right:
                    self.temp = self.temp.right
            else:
                if self.temp.right and self.temp.right.cnt:
                    self.ss += (1<<i)
                    self.temp = self.temp.right
                elif self.temp.left:
                    self.temp = self.temp.left
        return self.ss

q = int(input())
trie = Trie()
trie.insert(0)
for _ in range(0,q):
    qq = input().split()
    if qq[0] == '+':
        trie.insert(int(qq[1]))
    elif qq[0] == '-':
        trie.remove(int(qq[1]))
    else:
        print(trie.maxxor(int(qq[1])))





"""

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


10
? 1
+ 1
+ 8
- 1
+ 2
+ 7
+ 4
+ 7
+ 3
? 7




"""
