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.util.*;

public class Vasiliy {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int q = sc.nextInt();
		Trie root = new Trie();
		insert(0, 30, root);
		for (int i = 0; i < q; i++) {
			String sign = sc.next();
			int num = sc.nextInt();
			sc.nextLine();
			if (sign.charAt(0) == '+')
				insert(num, 30, root);
			else if (sign.charAt(0) == '-')
				delete(num, 30, root);
			else
				System.out.println(maxXor(num, 30, root));
		}
		sc.close();
	}

	private static class Trie {
		private static final int ALPHA = 2;

		private Trie[] children;
		private int count;

		public Trie() {
			this.children = new Trie[ALPHA];
			count = 0;
		}
	}

	public static void insert(int word, int i, Trie node) {
		if (i == -1) {
			return;
		}
		int bit = 1;
		if ((word & (1 << i)) == 0) 
			bit = 0;
		
		if (node.children[bit] == null) 
			node.children[bit] = new Trie();
		
		node.children[bit].count++;
		insert(word, i - 1, node.children[bit]);
	}

	public static void delete(int word, int i, Trie node) {
		if (i == -1) {
			return;
		}
		int bit = 1;
		if ((word & (1 << i)) == 0) 
			bit = 0;
		
		node.children[bit].count--;
		delete(word, i - 1, node.children[bit]);
	}

	public static int maxXor(int word, int i, Trie node) {
		if (i == 0) {
			if ((word & 1 << i) == 0) {
				return (node.children[1] == null || node.children[1].count == 0) ? 0 : 1;
			} else {
				return (node.children[0] == null || node.children[0].count == 0) ? 0 : 1;
			}
		} else if ((word & 1 << i) == 0) {
			return (node.children[1] == null || node.children[1].count == 0) ? maxXor(word, i - 1, node.children[0])
					: (maxXor(word, i - 1, node.children[1]) + (1 << i));
		} else {
			return (node.children[0] == null || node.children[0].count == 0) ? maxXor(word, i - 1, node.children[1])
					: (maxXor(word, i - 1, node.children[0]) + (1 << i));
		}
	}
   
}
