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 Problem706D {

	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		Trie trie = new Trie();
		trie.build(1, 0);
		int n = s.nextInt();
		for (int i = 0; i < n; i++) {
			String q = s.next();
			char op = q.charAt(0);
			int elem = s.nextInt();

			if (op == '+') {
				trie.build(1, elem);
			} else if (op == '-') {
				trie.build(-1, elem);
			} else {
				System.out.println(trie.search(elem));
			}
		}

	}

}

class Trie {
	final static int MAX = (int) 2e5 + 5;
	int next[][] = new int[MAX*30][2];
	int count[] = new int[MAX*30];
	int size;

	public Trie() {

		size = 0;
	}

	int getNewNode() {
		size++;
		return size;
	}

	void build(int op, int elem) {

		int now = 0;

		for (int index = 29; index >= 0; index--) {

			count[now] += op;
			int side = (elem >> index) & 1;
			int target;

			if (next[now][side] == 0) {
				target = getNewNode();
			} else {
				target = next[now][side];
			}
			next[now][side] = target;

			now = target;

		}
		count[now] += op;
		return;
	}

	int search(int query) {
		int now = 0;
		int ret = 0;
		for (int index = 29; index >= 0; index--) {

			int side = (query >> index) & 1;

			if (next[now][(side + 1) % 2] != 0 && count[next[now][(side + 1) % 2]] > 0) {
				side = (side + 1) % 2;
			}

			ret *= 2;
			ret += side;

			now = next[now][side];
		}

		return ret ^ query;
	}
}
