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.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.PrintStream;
import java.util.StringTokenizer;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Wolfgang Beyer
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskD solver = new TaskD();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskD {
        Node root;

        void insert(int n) {
            Node node = root;
            for (int i = 30; i >= 0; i--) {
                if (getBit(n, i)) {
                    if (node.left == null) {
                        node.left = new Node();
                    }
                    node = node.left;
                } else {
                    if (node.right == null) {
                        node.right = new Node();
                    }
                    node = node.right;
                }
            }
            node.freq++;
        }

        boolean removeRecursive(int n, Node currentNode, int level) {
            if (level < 0) {
                currentNode.freq--;
                if (currentNode.freq <= 0) {
                    return false;
                } else {
                    return true;
                }
            } else {
                if (getBit(n, level)) {
                    if (!removeRecursive(n, currentNode.left, level - 1)) {
                        currentNode.left = null;
                        if (currentNode.right == null) return false;
                    }
                } else {
                    if (!removeRecursive(n, currentNode.right, level - 1)) {
                        currentNode.right = null;
                        if (currentNode.left == null) return false;
                    }
                }
                return true;
            }
        }

        boolean getBit(int n, int k) {
            return 1 == ((n >> k) & 1);
        }

        int query(int n) {
            int result = 0;
            Node node = root;
            for (int i = 30; i >= 0; i--) {
                if ((node.left == null) || ((node.right != null) && (getBit(n, i)))) {
                    if (getBit(n, i)) result ^= 1 << i;
                    node = node.right;
                } else {
                    if (!getBit(n, i)) result ^= 1 << i;
                    node = node.left;
                }
            }
            return result;
        }

        public void solve(int testNumber, InputReader in, PrintWriter out) {
            int q = in.nextInt();
            root = new Node();
            insert(0);
            for (int i = 0; i < q; i++) {
                String s = in.next();
                int x = in.nextInt();

                if (s.equals("+")) insert(x);
                    //else if (s.equals("-")) remove(x);
                else if (s.equals("-")) removeRecursive(x, root, 30);
                else out.println(query(x));
            }
        }

        class Node {
            Node left;
            Node right;
            int freq;

            Node() {
                left = null;
                right = null;
                freq = 0;
            }

        }

    }

    static class InputReader {
        private static BufferedReader in;
        private static StringTokenizer tok;

        public InputReader(InputStream in) {
            this.in = new BufferedReader(new InputStreamReader(in));
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public String next() {
            try {
                while (tok == null || !tok.hasMoreTokens()) {
                    tok = new StringTokenizer(in.readLine());
                }
            } catch (IOException ex) {
                System.err.println("An IOException was caught :" + ex.getMessage());
            }
            return tok.nextToken();
        }

    }
}

