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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Random;
import java.util.StringTokenizer;

public class Solution{
	
	
    public static void main(String[] args) {
     
    	FastScanner fs = new FastScanner();
    	PrintWriter out = new PrintWriter(System.out);
    	
    		
    		
    	int tt = 1;
    	while(tt-->0) {
    	
    		
    		int q = fs.nextInt();
    		
    		Trie trie = new Trie();
    		trie.insert(0);
    		
    		while(q-->0) {
    			char ch = fs.nextChar();
    			int n = fs.nextInt();
    			switch(ch) {
    			case '+': 
    				trie.insert(n);
    				break;
    			case '-':
    				trie.delete(n);
    				break;
    			case '?':
    				out.println(trie.maxxor(n));
    				break;
    			}
    		}
    		
    		
    		
    		
    		
    	}
    	
    		
    		
    		
    	out.close();
    		
    }
    
    
    static class Node{
    	Node[] node = new Node[2];
    	int cnt = 0;
    }
    
    
    static class Trie{
    	Node root = new Node();
    	
    	void insert(int n) {
    		Node temp = root;
    		for(int i=29;i>=0;i--) {
    			int cur = ((n>>i)&1);
    			if(temp.node[cur]==null) {
    				temp.node[cur] = new Node();
    			}
    			temp = temp.node[cur];
    			temp.cnt++;
    		}
    	}
    	
    	void delete(int n) {
    		Node temp = root;
    		for(int i=29;i>=0;i--) {
    			int cur = ((n>>i)&1);
    			temp = temp.node[cur];
    			temp.cnt--;
    		}
    	}
    	
    	int maxxor(int x) {
    		Node temp = root;
    		int ans = 0;
    		for(int i=29;i>=0;i--) {
    			int cur = ((x>>i)&1);
    			if(temp.node[cur^1]!=null && temp.node[cur^1].cnt>0) {
    				ans += (1<<i);
    				temp = temp.node[cur^1];
    			}
    			else {
    				temp = temp.node[cur];
    			}
    		}
    		
    		return ans;
    		
    	}
    	
    	
    }
    
    
    
    
    static final Random random=new Random();
    	
    static void ruffleSort(int[] a) {
    	int n=a.length;//shuffle, then sort 
    	for (int i=0; i<n; i++) {
    		int oi=random.nextInt(n); int temp=a[oi];
    		a[oi]=a[i]; a[i]=temp;
    	}
    	Arrays.sort(a);
    }
   
  
    
    	
    	
    static class FastScanner{
    	BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    	StringTokenizer st = new StringTokenizer("");
     
    	public String next(){
    		while(!st.hasMoreElements()){
    			try{
    				st = new StringTokenizer(br.readLine());
    			} catch(IOException e){
    				e.printStackTrace();
    			}
    		}
    		return st.nextToken();
    	}
    		
    	public String nextLine() throws IOException {
    		return br.readLine();
    	}
    		
    	public int nextInt(){
    		return Integer.parseInt(next());
    	}
     
    	public int[] readArray(int n){
    		int[] a = new int[n];
    		for(int i=0;i<n;i++)
    			a[i] = nextInt();
    		return a;
    	}
    		
    	public long nextLong() {
    		return Long.parseLong(next());
    	}
    		
    	public char nextChar() {
    		return next().toCharArray()[0];
    	}
    }
   	
}