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.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.StringTokenizer;
import java.util.TreeMap;
import java.util.TreeSet;



public class Problem3 {
 

	public static void main(String[] args) throws InterruptedException {
		// TODO Auto-generated method stub
		InputStream inputStream = System.in;
		OutputStream outputStream = System.out;
		InputReader in = new InputReader(inputStream);
		PrintWriter out = new PrintWriter(outputStream);
		TrieNode root = new TrieNode(5);
		int q = in.nextInt();
		addNumber(root, get32BitString(0));
		
		for(int i = 0; i < q; ++i)
		{
			char op = in.next().charAt(0);
			int num = in.nextInt();
			String s = get32BitString(num);
			if(op == '+')
			{
				addNumber(root, s);
				
			}
			else if(op == '-')
			{
				delNumber(root, s);
			}
			else
			{
				int ans = 0;
				TrieNode node = root;
				for(int j = 0; j < s.length(); ++j)
				{
					if(s.charAt(j) == '0')
					{
						if(node.one != null && node.one.prefix > 0)
						{
							ans += (1<<(31 - j));
							node = node.one;
						}
						else if(node.zero != null)
						{
							node = node.zero;
						}
					}
					else if(s.charAt(j) == '1')
					{
						if(node.zero != null && node.zero.prefix > 0)
						{
							ans += (1<<(31 - j));
							node = node.zero;
						}
						else if(node.one != null )
						{
							node = node.one;
						}
					}
				}
				out.println(ans);
			}
		}
		
		
		
		out.close();

	}
	
	static class TrieNode
	{
		int bit;
		int prefix = 0;
		TrieNode one;
		TrieNode zero;
		public TrieNode(int bit)
		{
			this.bit = bit;
			one = null;
			zero = null;
		}
	}
	
	static void delNumber(TrieNode node, String num)
	{
		if(num.length() == 0)
		{
			return;
		}
		else
		{
			char k = num.charAt(0);
			if(k == '1')
			{
				node.one.prefix--;
				delNumber(node.one, num.substring(1));
			}
			else
			{
				node.zero.prefix--;
				delNumber(node.zero, num.substring(1));
			}
		}
	}
	
	static void addNumber(TrieNode node, String num)
	{
		if(num.length() == 0)
		{
			return;
		}
		else
		{
			char k = num.charAt(0);
			
			if(k == '1')
			{
				if(node.one == null)
				{
					node.one = new TrieNode(1);
				}
				node.one.prefix += 1;
				node.one.bit = k - '0';
				addNumber(node.one, num.substring(1));
			}
			else
			{
				if(node.zero == null)
				{
					node.zero = new TrieNode(0);
				}
				node.zero.prefix += 1;
				node.zero.bit = k - '0';
				addNumber(node.zero, num.substring(1));
			}
		}
	}
	
	static String get32BitString(int num)
	{
		String s = Integer.toBinaryString(num);
		int len = s.length();
		String temp = "";
		for(int i = 0; i < 32 - len; ++i)
		{
			temp += "0";
		}
		return temp + s;
	}
	
	
	

	

	static class InputReader {
	    public BufferedReader reader;
	    public StringTokenizer tokenizer;

	    public InputReader(InputStream stream) {
	        reader = new BufferedReader(new InputStreamReader(stream), 32768);
	        tokenizer = null;
	    }

	    public String next() {
	        while (tokenizer == null || !tokenizer.hasMoreTokens()) {
	            try {
	                tokenizer = new StringTokenizer(reader.readLine());
	            } catch (IOException e) {
	                throw new RuntimeException(e);
	            }
	        }
	        return tokenizer.nextToken();
	    }

	    public int nextInt() {
	        return Integer.parseInt(next());
	    }
	    
	    public long nextLong()
	    {
	    	return Long.parseLong(next());
	    }

	}


}