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.util.HashMap;
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 FinnTheHuman
 */
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 {
        HashMap<Integer, Integer> freqs = new HashMap<>();
        Node root;

        void insert(Node node, int x, int bit) {
            ++node.numberOfTerminals;
            if (bit == -1) {
                return;
            }
            if ((x & (1 << bit)) == 0) {
                if (node.children[0] == null) node.children[0] = new Node();
                insert(node.children[0], x, bit - 1);
            } else {
                if (node.children[1] == null) node.children[1] = new Node();
                insert(node.children[1], x, bit - 1);
            }
        }

        void erase(Node node, int x, int bit) {
            if (node == null) return;
            if ((x & (1 << bit)) == 0) {
                erase(node.children[0], x, bit - 1);
            } else {
                erase(node.children[1], x, bit - 1);
            }
            --node.numberOfTerminals;
        }

        int query(Node node, int x, int bit) {
            if (node == null || bit == -1) return 0;
            int contrary = (x & (1 << bit)) > 0 ? 0 : 1;
            if (node.children[contrary] != null && node.children[contrary].numberOfTerminals > 0) {
                return (1 << bit) + query(node.children[contrary], x, bit - 1);
            }
            return query(node.children[1 - contrary], x, bit - 1);
        }

        public void solve(int testNumber, InputReader in, PrintWriter out) {
            int q = in.nextInt();
            root = new Node();
            insert(root, 0, 31);
            for (int i = 0; i < q; ++i) {
                String queryType = in.next();
                int x = in.nextInt();
                if (queryType.equals("+")) {
                    int oldFreq = freqs.containsKey(x) ? freqs.get(x) : 0;
                    if (oldFreq == 0) insert(root, x, 31);
                    freqs.put(x, oldFreq + 1);
                } else if (queryType.equals("-")) {
                    int oldFreq = freqs.get(x);
                    if (oldFreq == 1) erase(root, x, 31);
                    freqs.put(x, oldFreq - 1);
                } else {
                    int ans = query(root, x, 31);
                    out.println(ans);
                }
            }
        }

        class Node {
            public Node[] children;
            public int numberOfTerminals;

            public Node() {
                this.numberOfTerminals = 0;
                this.children = new Node[2];
            }

        }

    }

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

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 65536 / 2);
            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());
        }

    }
}

