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.io.*;
public class Main
{
    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; 
        } 
    }
    static Trie root=new Trie();
    static class Pair
    {
        int f,s;
        Pair(int f,int s)
        {
            this.s=s;
            this.f=f;
        }
    }
    static class Trie
    {
        Trie child[]=new Trie[2];
        int cnt[]=new int[2];
        public static void insert(int a)
        {
            Trie cur=root;
            for(int i=30;i>=0;i--)
            {
                if((a&(1<<i))>0)
                {
                    if(cur.child[1]==null)
                    cur.child[1]=new Trie();
                    cur.cnt[1]++;
                    cur=cur.child[1];
                }
                else
                {
                    if(cur.child[0]==null)
                    cur.child[0]=new Trie();
                    cur.cnt[0]++;
                    cur=cur.child[0];
                }
            }
        }
        public static boolean remove(int bit,Trie cur,int a)
        {
            if(bit==-1)
            return true;
            Trie next=((1<<bit)&a)==0?cur.child[0]:cur.child[1];
            int nxt=((1<<bit)&a)==0?0:1;
            boolean shouldRemove=remove(bit-1,next,a);
            cur.cnt[nxt]--;
            if(shouldRemove&&cur.cnt[nxt]==0)
            {
                cur.child[nxt]=null;
                return true;
            }
            return false;
        }
        public static int query(int bit,int a,Trie node,int ans)
        {
            if(bit==-1)
            return ans;
            int nxt=((1<<bit)&a)==0?0:1;
            if(node.child[nxt^1]!=null)
            return query(bit-1,a,node.child[nxt^1],ans^(1<<bit));
            return query(bit-1,a,node.child[nxt],ans);
        }
    }
    public static void main(String args[])
    {
        FastReader fs=new FastReader();
        PrintWriter pw=new PrintWriter(System.out);
        int q=fs.nextInt();
        TreeMap<Integer,Integer> tmap=new TreeMap<>();
        root.insert(0);
        tmap.put(0,1);
        while(q-->0)
        {
            String str[]=fs.nextLine().split(" ");
            int num=Integer.parseInt(str[1]);
            if(str[0].equals("+"))
            {
                if(!tmap.containsKey(num))
                {
                    tmap.put(num,1);
                    root.insert(num);
                }
                else
                tmap.put(num,tmap.get(num)+1);
            }
            else if(str[0].equals("-"))
            {
                if(tmap.get(num)==1)
                {
                    tmap.remove(num);
                    root.remove(30,root,num);
                }
                else
                tmap.put(num,tmap.get(num)-1);
            }
            else
            {
                int xx=root.query(30,num,root,0);
                pw.println(Math.max(num,xx));
            }
        }
        pw.flush();
        pw.close();
    }
}