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.PrintWriter;
import java.util.StringTokenizer;

public class D {
	
	final static int HEIGHT = 30;
	public static void main(String[] args) {
		InputReader in = new InputReader(System.in);
        PrintWriter out = new PrintWriter(System.out);
        int n = in.nextInt();
        BiTrie tree = new BiTrie();
        tree.insert(convert(0));
        for(int i=0;i<n;i++){
        	String q = in.next();
        	int x = in.nextInt();
        	if(q.equals("+")){
        	    tree.insert(convert(x));
        	}
        	if(q.equals("-")){
        		tree.delete(convert(x));
        	}
        	if(q.equals("?")){
        		int y = back(tree.query(revert(convert(x))));
        		out.println(x ^ y);
        	}
        }
//        tree.root.print("");
        out.flush();
	}
	
	static String convert(int x){
		String str = Integer.toBinaryString(x);
		while(str.length()<HEIGHT) str = "0" + str;
		return str;
	}
	
	static String revert(String str){
		StringBuilder sb = new StringBuilder();
		for(int i=0;i<str.length();i++){
			if(str.charAt(i) == '0'){
				sb.append('1');
			} else {
				sb.append('0');
			}
		}
		return sb.toString();
	}
	static int back(String str){
		return Integer.parseInt(str, 2);
	}
	 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());
	        }

	    }
}
 
class BiTrie{
	BiNode root;
	
	public BiTrie() {
		this.root = new BiNode();
	}
	
	public void insert(String str){
		this.root.insert(str);
	}
	
	public void delete(String str){
		this.root.delete(str);
	}
	
	public String query(String str){
		return this.root.query(str);
	}
}

class BiNode{
	BiNode left;
	BiNode right;
	int val;
	public BiNode() {
		this.val = 0;
	}
	
	public void insert(String str){
		this.val++;
		if(str.equals("")) return;
		if(str.charAt(0) == '0'){
			if(this.left == null){
				this.left = new BiNode();
			}
			this.left.insert(str.substring(1));
		} else {
			if(this.right == null){
				this.right = new BiNode();
			}
			this.right.insert(str.substring(1));
		}
	}
	
	public void delete(String str){
		this.val--;
		if(str.equals("")) return;
		if(str.charAt(0) == '0'){
			if(this.left.val > 1){
				this.left.delete(str.substring(1));
			}else{
				this.left = null;
			}
		} else {
			if(this.right.val > 1){
				this.right.delete(str.substring(1));
			}else{
				this.right = null;
			}
		}
	}
	
	public String query(String str){
		if(str.equals("")) return "";
		if(str.charAt(0) == '0'){
			if(this.left != null){
				return "0" + this.left.query(str.substring(1));
			} else {
				return "1" + this.right.query(str.substring(1));
			}
		} else {
			if(this.right != null){
				return "1" + this.right.query(str.substring(1));
			} else {
				return "0" + this.left.query(str.substring(1));
			}
		}
	}
	
	public void print(String str){
		if(this.left != null){
			this.left.print(str + "0");
		}
		if(this.right != null){
			this.right.print(str + "1");
		}
		if(this.left == null && this.right == null){
			System.out.println(str + ": " + this.val);
		}
	}
}