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.FileReader;
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;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        DVasiliysMultiset solver = new DVasiliysMultiset();
        solver.solve(1, in, out);
        out.close();
    }

    static class DVasiliysMultiset {
        public void solve(int testNumber, Scanner sc, PrintWriter pw) {
            int q = sc.nextInt();
            Trie trie = new Trie();
            trie.insert(0);
            while (q-- > 0) {
                char c = sc.next().charAt(0);
                if (c == '+')
                    trie.insert(sc.nextInt());
                else if (c == '-')
                    trie.remove(sc.nextInt());
                else
                    pw.println(trie.getMax(sc.nextInt()));
            }
        }

        public class Trie {
            Node root;

            public Trie() {
                root = new Node();
            }

            public void insert(int x) {
                root.insert(x, 30);
            }

            public void remove(int x) {
                root.remove(x, 30);
            }

            public int getMax(int x) {
                return root.getMax(x, 30);
            }

        }

        public class Node {
            Node zero;
            Node one;
            int countOne;
            int countZero;

            public void insert(int x, int idx) {
                if (idx == -1)
                    return;
                int bit = (x & 1 << idx) == 0 ? 0 : 1;
                if (bit == 0) {
                    if (countZero == 0) {
                        zero = new Node();
                    }
                    countZero++;
                    zero.insert(x, idx - 1);
                } else {
                    if (countOne == 0)
                        one = new Node();
                    countOne++;
                    one.insert(x, idx - 1);
                }
            }

            public void remove(int x, int idx) {
                if (idx == -1)
                    return;
                int bit = (x & 1 << idx) == 0 ? 0 : 1;
                if (bit == 0) {
                    countZero--;
                    zero.remove(x, idx - 1);
                    if (countZero == 0)
                        zero = null;
                } else {
                    countOne--;
                    one.remove(x, idx - 1);
                    if (countOne == 0)
                        one = null;
                }
            }

            public int getMax(int x, int idx) {
                if (idx == -1)
                    return 0;
                if (zero == null)
                    return ((x & 1 << idx) != 0 ? 0 : 1 << idx) + one.getMax(x, idx - 1);
                if (one == null)
                    return (x & 1 << idx) + zero.getMax(x, idx - 1);
                int bit = (x & 1 << idx) == 0 ? 0 : 1;
                if (bit == 1)
                    return (1 << idx) + zero.getMax(x, idx - 1);
                else
                    return (1 << idx) + one.getMax(x, idx - 1);
            }

        }

    }

    static class Scanner {
        StringTokenizer st;
        BufferedReader br;

        public Scanner(FileReader r) {
            br = new BufferedReader(r);
        }

        public Scanner(InputStream s) {
            br = new BufferedReader(new InputStreamReader(s));
        }

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

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

    }
}

