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;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class Trie {
	static PrintWriter out;
	int value;
	Trie zero;
	Trie one;
	void insert(int x) {
		Trie cur = this;
		int i = 31;
		while(i >= 0) {
			int nextBool = x & (1 << i);
			Trie next = null;
			if(nextBool == 0) {
				if(cur.zero == null) {
					cur.zero = new Trie();
				}
				next = cur.zero;
			} else {
				if(cur.one == null) {
					cur.one = new Trie();
				}
				next = cur.one;	
			}
			next.value++;
			cur = next;
			i--;
		}
	}
	void delete(int x) {
		Trie cur = this;
		int i = 31;
		while(i >= 0) {
			int nextBool = x & (1 << i);
			Trie next = null;
			if(nextBool == 0) {
				next = cur.zero;
//				if(next.value > 1) {
					next.value--;
//				} else {
//					System.out.println(i);
//				}
			} else {
				next = cur.one;	
				next.value--;
			}
			cur = next;
			i--;
		}
	}
	int xorMax(int x) {
		int res = 0;		
		Trie cur = this;
		int i = 31;
		while(i >= 0) {
			int value = 1;
			int nextBool = x & (1 << i);
			Trie next = null;
			if(nextBool > 0) {
				next = cur.zero;
				if(next == null || next.value == 0) {
					next = cur.one;
					value = 0;
				}
			} else {
				next = cur.one;	
				if(next == null || next.value == 0) {
					next = cur.zero;
					value = 0;
				}		
			}
			res += value * Math.pow(2, i);
			cur = next;
			i--;
		}
		return res;
	}
	
	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
		out = new PrintWriter(System.out);
		int testCases = Integer.parseInt(bf.readLine());
		Trie trie = new Trie();
		trie.insert(0);
		while(testCases > 0) {
			StringTokenizer test = new StringTokenizer(bf.readLine());
			String operator = test.nextToken();
			if(operator.equals("+")) {
				trie.insert(Integer.parseInt(test.nextToken()));
			} else {
				if(operator.equals("-")) {
					trie.delete(Integer.parseInt(test.nextToken()));
				} else {
					if(operator.equals("?")) {
						out.println(trie.xorMax(Integer.parseInt(test.nextToken())));
					}
				}
			}
			testCases--;
		}
		out.flush();
		out.close();
	}
}
