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 {
        public void solve(int testNumber, InputReader in, PrintWriter out) {
            int MASK = 1 << 30;
            Node root = edit(null, MASK, 0, +1);

            int q = in.nextInt();
            for (int i = 0; i < q; i++) {
                String type = in.next();
                int num = in.nextInt();

                if ("+".equals(type)) {
                    root = edit(root, MASK, num, +1);
                } else if ("-".equals(type)) {
                    root = edit(root, MASK, num, -1);
                } else {
                    out.println(find(root, MASK, num, 0));
                }
            }
        }

        private Node edit(Node n, int mask, int val, int change) {
            if (n == null) {
                n = new Node();
            }

            if (mask == 0) {
                n.size += change;
                return n;
            }

            if ((mask & val) > 0) {
                n.right = edit(n.right, mask / 2, val, change);
            } else {
                n.left = edit(n.left, mask / 2, val, change);
            }
            n.size += change;
            return n;
        }

        private int find(Node n, int mask, int val, int ans) {
            if (mask == 0) {
                return ans;
            }

            if ((mask & val) > 0) {
                if (size(n.left) > 0) {
                    return find(n.left, mask / 2, val, ans | mask);
                } else {
                    return find(n.right, mask / 2, val, ans);
                }
            } else {
                if (size(n.right) > 0) {
                    return find(n.right, mask / 2, val, ans | mask);
                } else {
                    return find(n.left, mask / 2, val, ans);
                }
            }
        }

        private int size(Node n) {
            return n == null ? 0 : n.size;
        }

        private static class Node {
            private int size;
            private Node left;
            private Node right;

        }

    }

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

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            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());
        }

    }
}

