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.InputStreamReader;

public class Main1 {
	public static void main(String[] args) throws NumberFormatException, IOException {
		MaxXorBinaryTrie mxbt = new MaxXorBinaryTrie();
		mxbt.insert(0);
		
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		
		int numberOfQueries = Integer.parseInt(in.readLine());
		
		for (int i = 0; i < numberOfQueries; i++) {
			String[] words = in.readLine().split(" ");
			char operation = words[0].charAt(0);
			int number = Integer.parseInt(words[1]);
			
			switch (operation) {
			case '+':
				mxbt.insert(number);
				break;
			case '-':
				mxbt.delete(number);
				break;
			case '?':
				System.out.println(mxbt.getMaxXor(number));
			}
		}
	}
	
	// Shitty implementation
	static class MaxXorBinaryTrie {
		static class Node {
			int count;
			Integer value = null;
			Node[] children = new Node[2];
		}
		
		Node root = new Node();
		
		void insert(int number) {
			Node currentNode = this.root;
			
			for(int i = 1 << 30; i > 0; i >>= 1) {
				currentNode.count++;
				
				int index = (number & i) > 0? 1 : 0;
				
				if (currentNode.children[index] == null) {
					currentNode.children[index] = new Node();
				}
				
				currentNode = currentNode.children[index];
			}
			
			currentNode.count++;
			currentNode.value = number;
		}
		
		void delete(int number) {
			Node currentNode = this.root;
			
			for(int i = 1 << 30; i > 0; i >>= 1) {
				currentNode.count--;
				
				int index = (number & i) > 0? 1 : 0;
				
				if (currentNode.children[index] == null) {
					throw new RuntimeException("This is bullshit you promised you wouldn't do this");
				}
				
				currentNode = currentNode.children[index];
			}
			
			currentNode.count--;
		}
		
		
		int getMaxXor(int other) {
			Node currentNode = this.root;
			
			for(int i = 1 << 30; i > 0; i >>= 1) {
				int minIndex = (other & i) > 0? 1 : 0;
				int maxIndex = minIndex ^ 1;
				
				if (currentNode.children[maxIndex] != null
						&& currentNode.children[maxIndex].count > 0) {
					currentNode = currentNode.children[maxIndex];
				} else if(currentNode.children[minIndex] != null
						&& currentNode.children[minIndex].count > 0) {
					currentNode = currentNode.children[minIndex];
				} else {
					throw new RuntimeException("You queried an empty trie, dipshit");
				}
			}
			
			return currentNode.value ^ other;
		}
	}
}
