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.BufferedWriter;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.StringTokenizer;

public class Main {

	static class Node {
		short count;
		Node[] next;
		Node[] previous;

		public Node() {
			next = new Node[2];
			previous = new Node[2];
			count = 0;
		}
		
		public void setNext(int i, Node nextNode) {
			next[i] = nextNode;
			nextNode.previous[i] = this;
		}
		
		public void removeNext(int i) {
			next[i].previous[i] = null;
			next[i] = null;
		}
		
		public String toString() {
			return "{(" + count + ")" + next[0] + "|" + next[1] + "}"; 
		}
	}

	static class Trei {

		Node root;

		public Trei() {
			root = new Node();
		}

		public void add(int x) {
			Node current = root;
			for(int i = 30; i >= 0; i--) {
				int bit = (x >> i) % 2;
				if(current.next[bit] != null)
					current = current.next[bit];
				else {
					current.setNext(bit, new Node());
					current = current.next[bit];
				}
			}
			current.count++;
		}

		public void remove(int x) {
			Node current = root;
			for(int i = 30; i >= 0; i--) {
				int bit = (x >> i) % 2;
				current = current.next[bit];
			}
			
			if(current.count > 1) {
				current.count--;
				return;
			}
			for(int i = 0; i <= 30; i++) {
				int bit = (x >> i) % 2;
				current = current.previous[bit];
				current.removeNext(bit);
				if(current.count > 0 || current.next[bit^1] != null) {
					return;
				}
			}
			
		}
		
		public int maxXOR(int x) {
			Node current = root;
			int y = 0;
			int optimal = ~x & Integer.MAX_VALUE;
			for(int i = 30; i >= 0; i--) {
				y <<= 1;
				int bit = (optimal >> i) % 2;
				if(current.next[bit] != null) {
					y |= bit;
					current = current.next[bit];
				} else if(current.next[bit^1] != null) {
					y |= bit^1;
					current = current.next[bit^1];
				} else {
				}
			}
			return x^y;
		}
	}

	public static void main(String[] args) throws Exception {
		Trei t = new Trei();
		t.add(0);
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
		int n = Integer.parseInt(br.readLine());
		for(int i = 0; i < n; i++) {
			StringTokenizer st = new StringTokenizer(br.readLine());
			String operator = st.nextToken();
			int x = Integer.parseInt(st.nextToken());
			switch(operator) {
			case "+":
				t.add(x);
				break;
			case "-":
				t.remove(x);
				break;
			case "?":
				bw.write("" + t.maxXOR(x));
				bw.newLine();
				break;
			}
		}
		br.close();
		bw.close();
	}
}
