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.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

public class CF_367D {

	static long answer;

	static class Trie {
		int ROOT = 0;
		int idx = 0;
		int MAXN = (int) (64e5);
		int[][] trie;
		int cnt[];

		Trie() {
			trie = new int[MAXN][2];
			for (int i = 0; i < MAXN; i++)
				Arrays.fill(trie[i], -1);
			cnt = new int[MAXN];
		}

		void edit(int num, int d) {
			int cur = ROOT;
			for (int i = 31; i >= 0; i--) {
				int bit = num & (1 << i);
				bit = (bit > 0 ? 1 : 0);
				if (trie[cur][bit] == -1)
					trie[cur][bit] = ++idx;
				cur = trie[cur][bit];
				cnt[cur] += d;
			}
		}

		void search(int num) {
			int cur = ROOT;
			for (int i = 31; i >= 0; i--) {
				int bit = num & (1 << i);
				bit = (bit > 0 ? 1 : 0);
				int edge2 = trie[cur][bit];
				int edge1 = trie[cur][bit == 0 ? 1 : 0];
				if (edge1 != -1 && cnt[edge1] > 0) {
					answer |= (1 << i);
					cur = edge1;
				} else if (edge2 != -1 && cnt[edge2] > 0) {
					cur = edge2;
				}
			}
		}
	}

	public static void main(String[] args) throws NumberFormatException, IOException {
		Scanner sc = new Scanner();
		PrintWriter out = new PrintWriter(System.out);
		int q = sc.nextInt();
		Trie trie = new Trie();
		trie.edit(0, 1);
		while (q-- > 0) {
			String t = sc.next();
			int x = sc.nextInt();
			if (t.equals("+")) {
				trie.edit(x, 1);
			} else if (t.equals("-")) {
				trie.edit(x, -1);
			} else {
				answer = 0;
				trie.search(x);
				out.println(answer);
			}
		}

		out.flush();
		out.close();
	}

	static class Scanner {
		BufferedReader br;
		StringTokenizer st;

		Scanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		Scanner(String file) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(file));
		}

		Boolean ready() throws IOException {
			return br.ready();
		}

		String next() throws IOException {
			while (st == null || !st.hasMoreTokens())
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}

		int nextInt() throws NumberFormatException, IOException {
			return Integer.parseInt(next());
		}

		String nextLine() throws IOException {
			return br.readLine();
		}

		long nextLong() throws NumberFormatException, IOException {
			return Long.parseLong(next());
		}

		Double nextDouble() throws NumberFormatException, IOException {
			return Double.parseDouble(next());
		}

	}

}
