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.*;
import java.util.*;
import java.math.*;
import java.text.*;
 
public class Solution {
    
    static FastReader sc=new FastReader();
    
    class TrieNode{
        TrieNode child[]=new TrieNode[2];
        TrieNode parent;
    }
    
    TrieNode root=new TrieNode();
    int level=31;
    
    void run() {
        int q=sc.nextInt();
        Map<Integer,Integer> map=new HashMap<Integer,Integer>();
        addToTrie(0);
        StringBuilder str=new StringBuilder();
        while(q-->0){
            String ch=sc.next();
            int x=sc.nextInt();
            if(ch.equals("+")){
                int freq=map.getOrDefault(x,0);
                map.put(x,freq+1);
                if(freq==0){
                    addToTrie(x);
                }
            }else if(ch.equals("-")){
                int freq=map.get(x)-1;
                map.put(x,freq);
                if(freq==0){
                    removeFromTrie(x);
                }
            }else{
                str.append(String.valueOf(queryTrie(x))+"\n");
            }
        }
        System.out.print(str);
    }
    
    void addToTrie(int x){
        TrieNode tmp=root;
        for(int i=level;i>=0;i--){
            TrieNode p=tmp;
            int node=0;
            if((x&(1<<i))!=0)
                node=1;
            if(tmp.child[node]==null)
                tmp.child[node]=new TrieNode();
            tmp=tmp.child[node];
            tmp.parent=p;
        }
    }
    
    void removeFromTrie(int x){
        TrieNode tmp=root;
        for(int i=level;i>=0;i--){
            int node=0;
            if((x&(1<<i))!=0){
                node=1;
            }
            tmp=tmp.child[node];
        }
        
        for(int i=0;i<=level;i++){
            tmp=tmp.parent;
            int node=0;
            if((x & (1<<i))!=0)
                node=1;
            tmp.child[node]=null;
            int other=(node^1);
            if(tmp.child[other]!=null)
                break;
        }
    }
    
    int queryTrie(int x){
        TrieNode tmp=root;
        int ans=0;
        for(int i=level;i>=0 && tmp!=null;i--){
            int node=1;
            if((x &(1<<i))!=0){
                node=0;
            }
            
            if(tmp.child[node]!=null){
               ans+=(1<<i);
            }else{
               node=node^1;
            }
            tmp=tmp.child[node];
        }
        return ans;
    }
    
    public static void main(String args[]) throws IOException {
        new  Solution().run();
    }
    
    static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            br = new BufferedReader(new
                     InputStreamReader(System.in)); 
        } 
  
            String next() 
        { 
            while (st == null || !st.hasMoreElements()) 
            { 
                try
                { 
                    st = new StringTokenizer(br.readLine()); 
                } 
                catch (IOException  e) 
                { 
                    e.printStackTrace(); 
                } 
            } 
            return st.nextToken(); 
        } 
  
        int nextInt() 
        { 
            return Integer.parseInt(next()); 
        } 
  
        long nextLong() 
        { 
            return Long.parseLong(next()); 
        } 
  
        double nextDouble() 
        { 
            return Double.parseDouble(next()); 
        } 
  
        String nextLine() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine(); 
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    }
 
}



