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>.
/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
public final class Main {

    public static void main(String[] args)  {
        Scanner file = new Scanner(System.in);
        int tests = file.nextInt();
        Trie root = new Trie();
        root.adder(0,31);

        for (int i = 0; i < tests; ++i) {
            String q = file.next();
            int x = file.nextInt();
            if (q.equals("+")){
                root.adder(x,31);
            } 
            else if(q.equals("-")){
                root.remover(x,31);
            } 
            else {
                System.out.println(x^root.xorMax(x,31));
            }
        }
    }
}

class Trie{

    Trie[] children;
    int instances;

    public Trie(){
        children = new Trie[2];
        instances=0;
    }

    public void adder(int n, int x){
        if (x < 0){	//base case
            ++instances;
            return;
        }

        int bit = 1;
        if ((n & (1 << x)) == 0) 
	bit = 0;
        if(children[bit] == null){
            children[bit] = new Trie();
        }
        children[bit].adder(n, x - 1);
    }
    public boolean remover(int n, int x){
        if (x < 0){//base case
            --instances;
            return instances==0;
        }

	int bit = 1;
	if ((n & (1 << x)) == 0) 
		bit = 0;
        boolean result = children[bit].remover(n, x - 1);
        if (result){
            children[bit] = null;
            return children[1 - bit] == null;
        }
        return false;
    }
    public int xorMax(int n, int x){
        if (x < 0){//base case
            return 0;
        }
        int bit = 1;
        if ((n & (1 << x)) == 0) 
	bit = 0;
        int bit1 = 0;
        if(children[1 - bit] != null)
	bit1 = 1-bit;
        else
	bit1=bit;
        int result = children[bit1].xorMax(n, x - 1);
        return result + (bit1 << x);
    }
}