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.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
 */
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 {
        private int[] mask = new int[31];
        TaskD.Node root = new TaskD.Node();

        private void add(int x) {
            TaskD.Node node = root;
            for (int i = mask.length - 1; i >= 0; i--) {
                node.cnt++;
                if ((x & (1 << i)) > 0) {
                    if (node.one == null) node.one = new TaskD.Node();
                    node = node.one;
                } else {
                    if (node.zero == null) node.zero = new TaskD.Node();
                    node = node.zero;
                }
            }
            node.cnt++;
        }

        private void del(int x) {
            TaskD.Node node = root;
            for (int i = mask.length - 1; i >= 0; i--) {
                if (node == null) return;
                node.cnt--;
                if ((x & (1 << i)) > 0) {
                    if (node.one.cnt <= 1) node.one = null;
                    node = node.one;
                } else {
                    if (node.zero.cnt <= 1) node.zero = null;
                    node = node.zero;
                }
            }
            if (node != null) {
                node.cnt--;
            }
        }

        private int query(int x) {
            TaskD.Node node = root;
            int ans = 0;
            for (int i = mask.length - 1; i >= 0; i--) {
                if (node.one == null && node.zero == null) {
                    if ((x & (1 << i)) > 0) {
                        ans += 1 << i;
                    }
                    continue;
                }
                if ((x & (1 << i)) > 0) {
                    if (node.zero != null) {
                        ans += 1 << i;
                        node = node.zero;
                    } else {
                        node = node.one;
                    }
                } else {
                    if (node.one != null) {
                        ans += 1 << i;
                        node = node.one;
                    } else {
                        node = node.zero;
                    }
                }
            }
            return ans;
        }

        public void solve(int testNumber, InputReader in, PrintWriter out) {
            int q = in.nextInt();
            for (int i = 0; i < mask.length; i++) {
                mask[i] = 1 << i;
            }
            for (int i = 0; i < q; i++) {
                String s = in.next();
                int v = in.nextInt();
                if (s.equals("+")) {
                    add(v);
                } else if (s.equals("-")) {
                    del(v);
                } else {
                    // "?"
                    out.println(Math.max(v, query(v)));
                }
            }
        }

        static class Node {
            TaskD.Node zero = null;
            TaskD.Node one = null;
            int cnt = 0;

        }

    }

    static class InputReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream));
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

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

    }
}

