human
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 , 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  — maximum among integers , , ,  and .
Solve the task in PYTHON3.

Write me a Python code to print one integer — the maximum value of bitwise exclusive OR (XOR) of integer xi and some integer from the multiset A?
assistant
#Here is Python code to print one integer — the maximum value of bitwise exclusive OR (XOR) of integer xi and some integer from the multiset A.

# by the authority of GOD     author: manhar singh sachdev #

import os,sys
from io import BytesIO,IOBase

class Node:
    def __init__(self):
        self.zero = None
        self.one = None
        self.onpath = 0

class Trie:
    def __init__(self, node):
        self.root = node

    def add(self, num):
        curr = self.root
        for bit in num:
            if bit == '1':
                if not curr.one:
                    curr.one = Node()
                curr = curr.one
            else:
                if not curr.zero:
                    curr.zero = Node()
                curr = curr.zero
            curr.onpath += 1

    def findmaxxor(self, num):
        curr,val = self.root,0
        for i in num:
            if not curr:
                val *= 2
                continue
            z = '0' if i == '1' else '1'
            if z == '1':
                if curr.one:
                    curr = curr.one
                    val = val*2+1
                else:
                    curr = curr.zero
                    val *= 2
            else:
                if curr.zero:
                    curr = curr.zero
                    val = val*2+1
                else:
                    curr = curr.one
                    val *= 2
        return val

    def __delitem__(self, num):
        curr = self.root
        for bit in num:
            if bit == '1':
                if curr.one.onpath == 1:
                    curr.one = None
                    break
                curr = curr.one
            else:
                if curr.zero.onpath == 1:
                    curr.zero = None
                    break
                curr = curr.zero
            curr.onpath -= 1

def main():
    z = Trie(Node())
    z.add('0' * 30)
    for _ in range(int(input())):
        r = input().split()
        x = bin(int(r[1]))[2:].zfill(30)
        if r[0] == '+':
            z.add(x)
        elif r[0] == '-':
            del z[x]
        else:
            print(z.findmaxxor(x))

# Fast IO Region
BUFSIZE = 8192
class...