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.*;
import java.util.StringTokenizer;

/**
 * _706D
 * O(q*log(10^9)) time
 * O(q*log(10^9)) space
 *
 * @author artyom
 */
public class _706D implements Runnable {
    private BufferedReader in;
    private PrintStream out;
    private StringTokenizer tok;

    private void solve() throws IOException {
        Node trie = new Node(), t = trie;
        for (int i = 0; i < 30; i++) {
            t = t.left = new Node();
        }

        StringBuilder sb = new StringBuilder();
        for (int i = 0, q = nextInt(); i < q; i++) {
            String s = nextToken();
            int x = nextInt();
            t = trie;
            switch (s) {
                case "+":
                    for (int b = 1 << 29; b > 0; b >>= 1) {
                        if ((x & b) == b) {
                            if (t.right == null) {
                                t.right = new Node();
                            } else {
                                t.right.count++;
                            }
                            t = t.right;
                        } else {
                            if (t.left == null) {
                                t.left = new Node();
                            } else {
                                t.left.count++;
                            }
                            t = t.left;
                        }
                    }
                    break;
                case "-":
                    for (int b = 1 << 29; b > 0; b >>= 1) {
                        if ((x & b) == b) {
                            if (--t.right.count == 0) {
                                t.right = null;
                                break;
                            }
                            t = t.right;
                        } else {
                            if (--t.left.count == 0) {
                                t.left = null;
                                break;
                            }
                            t = t.left;
                        }
                    }
                    break;
                case "?":
                    int xor = 0;
                    for (int b = 1 << 29; b > 0; b >>= 1) {
                        if ((x & b) == b) {
                            if (t.left != null) {
                                xor += b;
                                t = t.left;
                            } else {
                                t = t.right;
                            }
                        } else {
                            if (t.right != null) {
                                xor += b;
                                t = t.right;
                            } else {
                                t = t.left;
                            }
                        }
                    }
                    sb.append(xor).append('\n');
            }
        }
        out.print(sb);
    }

    //--------------------------------------------------------------
    public static void main(String[] args) {
        new _706D().run();
    }

    @Override
    public void run() {
        try {
            in = new BufferedReader(new InputStreamReader(System.in));
            out = System.out;
            tok = null;
            solve();
            in.close();
        } catch (IOException e) {
            System.exit(0);
        }
    }

    private String nextToken() throws IOException {
        while (tok == null || !tok.hasMoreTokens()) {
            tok = new StringTokenizer(in.readLine());
        }
        return tok.nextToken();
    }

    private int nextInt() throws IOException {
        return Integer.parseInt(nextToken());
    }

    private static final class Node {
        Node left;
        Node right;
        int count = 1;
    }
}