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 static java.lang.Math.* ;
import static java.util.Arrays.* ;

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

public class D{


    void main() throws Exception {
        Scanner sc = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        Trie t = new Trie() ;
        t.add(0);
        int q = sc.nextInt() ;
        while(q-->0)
        {
            char c = sc.next().charAt(0) ;
            int x = sc.nextInt();
            if(c == '+')
                t.add(x);
            else if(c == '-')
                t.delete(x);
            else
                out.println(x ^ t.getMax(x));
        }
        out.flush();
        out.close();
    }

    class Node
    {
        Node [] elements ;
        int [] freq ;
        Node()
        {
            elements = new Node [2] ;
            freq = new int [2] ;
        }
    }
    class Trie
    {
        Node root ;

        Trie()
        {
            root = new Node() ;
        }

        void add(int x) {
            Node traverse = root ;
            for(int i = 29 ; i >= 0 ; i--)
            {
                if((x & (1 << i)) == 0)
                {
                    if(traverse.elements[0] == null)
                        traverse.elements[0] = new Node() ;
                    traverse = traverse.elements[0] ;
                    traverse.freq[0] ++ ;
                }
                else
                {
                    if(traverse.elements[1] == null)
                        traverse.elements[1] = new Node() ;
                    traverse = traverse.elements[1] ;
                    traverse.freq[1] ++ ;
                }
            }
        }
        boolean check(int x)
        {
            Node traverse = root ;
            for(int i = 29 ; i >= 0 ; i--)
            {
                if((x & (1 << i)) == 0)
                {
                    if(traverse.elements[0] == null)return false ;
                    traverse = traverse.elements[0] ;
                    if(traverse.freq[0] == 0)return false ;
                }
                else
                {
                    if(traverse.elements[1] == null)return false ;
                    traverse = traverse.elements[1] ;
                    if(traverse.freq[1] == 0)return false ;
                }
            }
            return true ;
        }
        void delete(int x)
        {
            if(!check(x))return;

            Node traverse = root ;
            for(int i = 29 ; i >= 0 ; i--)
            {
                if((x & (1 << i)) == 0)
                {
                    traverse = traverse.elements[0] ;
                    traverse.freq[0] -- ;
                }
                else
                {
                    traverse = traverse.elements[1] ;
                    traverse.freq[1] -- ;
                }
            }
        }
        int getMax(int x)
        {
            Node traverse = root ;
            int ans = 0 ;
            for(int i = 29 ; i >= 0 ; i--)
            {
                if(traverse == null) return ans ;
                if((x & (1 << i)) == 0)
                {
                    if(traverse.elements[1] != null && traverse.elements[1].freq[1] > 0)
                    {
                        ans |= 1 << i ;
                        traverse = traverse.elements[1] ;
                    }
                    else if(traverse.elements[0] != null && traverse.elements[0].freq[0] > 0)
                        traverse = traverse.elements[0] ;
                    else
                        return ans ;
                }
                else
                {
                    if(traverse.elements[0] != null && traverse.elements[0].freq[0] > 0)
                        traverse = traverse.elements[0] ;

                    else if(traverse.elements[1] != null && traverse.elements[1].freq[1] > 0) {
                        ans |= 1 << i ;
                        traverse = traverse.elements[1];
                    }
                    else
                        return ans ;
                }
            }
            return ans ;
        }

    }
    class Scanner
    {
        BufferedReader br;
        StringTokenizer st;

        Scanner(InputStream in)
        {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() throws Exception
        {
            while (st == null || !st.hasMoreTokens())
                st = new StringTokenizer(br.readLine());
            return st.nextToken();
        }

        int nextInt() throws Exception { return Integer.parseInt(next()); }

        long nextLong() throws Exception { return Long.parseLong(next()); }

        double nextDouble() throws Exception { return Double.parseDouble(next());}
    }

    public static void main (String [] args) throws Exception {(new D()).main();}

}