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 class Ideone
{
	static int n;
	static node trie;
	static Map<Integer, Integer> cnt;
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		n = Integer.parseInt(in.readLine());
		cnt = new HashMap<Integer, Integer>();
		trie = new node();
		String zero = Integer.toBinaryString(-1);
		trie.add(zero,0);
		StringTokenizer st;
		for(int i = 0; i < n; i++) {
			st = new StringTokenizer(in.readLine());
			char type = st.nextToken().charAt(0);
			int num = Integer.parseInt(st.nextToken());
			String bits = Integer.toBinaryString(~num);
			//System.out.println(bits);
			if(type == '+') {
				trie.add(bits,0);
			} else if(type == '-') {
				trie.delete(bits,0);
			} else {
				System.out.print(trie.best(bits,0,0) + "\n");
			}
		}
	}
}
class node {
	node[] arr;
	int cnt;
	public node() {
		arr = new node[2];
		cnt = 1;
	}
	public void add(String s, int idx) {
		if(idx == s.length()) return;
		int val = s.charAt(idx) - '0';
		if(arr[val] == null) {
			arr[val] = new node();
		} else {
			arr[val].cnt++;
		}
		arr[val].add(s, idx + 1);
	}
	public void delete(String s, int idx) {
		if(idx == s.length()) return;
		int val = s.charAt(idx) - '0';
		if(arr[val] == null) {
			System.out.println("wtf");
			return;
		} else {
			if(arr[val].cnt == 1) {
				arr[val] = null;
				return;
			} else {
				arr[val].cnt--;
			}
		}
		arr[val].delete(s, idx + 1);
	}
	public int best(String s, int idx, int cur) {
		if(idx == s.length()) {
			return cur;
		}
		int val = s.charAt(idx) - '0';
		if(arr[val ^ 1] == null && arr[val] == null) {
			System.out.println("wtf2");
			return 0;
		}
		if(arr[val ^ 1] != null) {
			return arr[val ^ 1].best(s, idx + 1, 2*cur + 1);
		} else {
			return arr[val].best(s, idx + 1,2*cur);
		}
	}
}