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

public class D {

	static class Node {

		Node zero = null;
		Node one = null;
		int cant = 0;
	}

	static int limit = 30;

	static Node root;

	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		root = new Node();
		root.cant++;
		Node cur = root;
		for (int i = 0; i < limit; i++) {
			cur.zero = new Node();
			cur = cur.zero;
			cur.cant++;
		}

		int q = Integer.parseInt(br.readLine());

		PrintWriter out = new PrintWriter(System.out);
		for (int qq = 0; qq < q; qq++) {
			StringTokenizer row = new StringTokenizer(br.readLine());
			String smb = row.nextToken();
			int n = Integer.parseInt(row.nextToken());
			if (smb.equals("+")) {
				add(n);
			} else if (smb.equals("-")) {
				remove(n);
			} else {
				boolean[] bin = bin(n);
				Node curr = root;
				long ret = 0;
				for (int i = bin.length - 1; i >= 0; i--) {
					if (bin[i] && curr.zero != null && curr.zero.cant > 0) {
						curr = curr.zero;
						ret += 1 << i;
					} else if (!bin[i] && curr.one != null && curr.one.cant > 0) {
						curr = curr.one;
						ret += 1 << i;
					} else if (bin[i] && curr.one != null && curr.one.cant > 0) {
						curr = curr.one;
					} else if (!bin[i] && curr.zero != null && curr.zero.cant > 0) {
						curr = curr.zero;
					} else {
						break;
					}
				}
				out.write(Long.toString(ret));
				out.write("\n");
			}
		}
		out.close();
	}

	private static Node add(int n) {
		boolean[] bin = bin(n);
		Node cur = root;
		for (int i = bin.length - 1; i >= 0; i--) {
			if (bin[i]) {
				if (cur.one == null) {
					cur.one = new Node();
				}
				cur = cur.one;
			} else {
				if (cur.zero == null) {
					cur.zero = new Node();
				}
				cur = cur.zero;
			}
			cur.cant++;
		}
		return cur;
	}

	private static Node remove(int n) {
		boolean[] bin = bin(n);
		Node cur = root;
		for (int i = bin.length - 1; i >= 0; i--) {
			if (bin[i]) {
				if (cur.one == null) {
					cur.one = new Node();
				}
				cur = cur.one;
			} else {
				if (cur.zero == null) {
					cur.zero = new Node();
				}
				cur = cur.zero;
			}
			cur.cant--;
		}
		return cur;
	}

	private static boolean[] bin(int n) {
		boolean[] b = new boolean[limit];
		for (int i = 0; i < limit; i++) {
			b[i] = (n & (1 << i)) != 0;
		}
		return b;
	}

}
