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


public class Trie { 
      
    static class Node {
		Node[] children = new Node[2];
		boolean end = false;
		int nChildren = 0;
		
		void add(int v, int b) {
			if(b == -1){
				 nChildren++;
				 return;
			}
			int bit = (v & (1 << b)) != 0 ? 1 : 0;
			if(children[bit] == null)
				children[bit] = new Node();
			children[bit].add(v, b-1);
			nChildren++;
		}
		
		void remove(int v, int b) {
			if(b == -1){
				 nChildren--;
				 return;
			}
			int bit = (v & (1 << b)) != 0 ? 1 : 0;
			children[bit].remove(v, b-1);
			nChildren--;
		}
		
		int query(int v, int b) {
			if(b == -1){
				 return 0;
			}
			int bit = (v & (1 << b)) != 0 ? 1 : 0;
			int ret = 0;
			if (children[1-bit] != null && children[1-bit].nChildren > 0) {
				ret = children[1-bit].query(v, b-1) | (1 << b);
				//System.out.println(b + " ");
			}
			else if (children[bit] != null && children[bit].nChildren > 0) {
				ret = children[bit].query(v, b-1);
			}
			return ret;
		}
	}
	
	
	
	
	 public static void main(String args[]) {
		Node root = new Node();
		Scanner reader = new Scanner(System.in);
		int n = reader.nextInt();
		//reader.next();
		root.add(0, 31);
		for(int i=0;i<n;i++) {
			StringTokenizer st = new StringTokenizer(reader.next());
			String s1=st.nextToken();
			//System.out.println(s1);
			char k = s1.charAt(0);
			int v = Integer.parseInt(reader.next());
			if(k == '+')
				root.add(v, 31);
			if(k == '-')
				root.remove(v, 31);
			if(k == '?')
				System.out.println(root.query(v, 31));
		}
		
	}
         
    } 
