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.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class DTask {

    private static int[] arr = new int[32];

    public static void main(String[] args) throws IOException {
        MyInputReader in = new MyInputReader(System.in);
        Node root = new Node(Integer.MAX_VALUE, false, null, null);
        Node cur = root;
        for (int i = 0; i < 32; i++) {
            cur.left = new Node(Integer.MAX_VALUE, false, null, null);
            cur = cur.left;
        }
        int q = in.nextInt();
        for (int i = 0; i < q; i++) {
            String sign = in.next();
            int value = in.nextInt();
            if (sign.equals("+")) {
                add(root, value);
            } else if (sign.equals("-")) {
                delete(root, value);
            } else {
                ask(root, value);
            }
        }
    }

    private static void ask(Node root, int value) {
        str(value);
        int acc = 0;
        Node cur = root;
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] == 1) {
                if (cur.left != null) {
                    cur = cur.left;
                    acc += 1 << (31 - i);
                } else {
                    cur = cur.right;
                }
            } else {
                if (cur.right != null) {
                    cur = cur.right;
                    acc += 1 << (31 - i);
                } else {
                    cur = cur.left;
                }
            }
        }
        System.out.println(acc);
    }

    private static void delete(Node root, int value) {
        str(value);
        Node cur = root;
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] == 1) {
                if (cur.right == null) {
                    break;
                }
                cur.right.count -= 1;
                if (cur.right.count == 0) {
                    cur.right = null;
                    break;
                }
                cur = cur.right;
            } else {
                if (cur.left == null) {
                    break;
                }
                cur.left.count -= 1;
                if (cur.left.count == 0) {
                    cur.left = null;
                    break;
                }
                cur = cur.left;
            }
        }
    }

    private static void add(Node root, int value) {
        str(value);
        Node cur = root;
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] == 1) {
                if (cur.right == null) {
                    cur.right = new Node(0, true, null, null);
                }
                cur.right.count += 1;
                cur = cur.right;
            } else {
                if (cur.left == null) {
                    cur.left = new Node(0, false, null, null);
                }
                cur.left.count += 1;
                cur = cur.left;
            }
        }
    }

    static void str(int v) {
        for (int i = 0; i < 32; i++) {
            arr[31 - i] = ((v & (1 << i)) > 0) ? 1 : 0;
        }
    }

    static class Node {

        int count;
        boolean one;
        Node left;
        Node right;

        public Node(int count, boolean one, Node left, Node right) {
            this.count = count;
            this.one = one;
            this.left = left;
            this.right = right;
        }
    }

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

        public MyInputReader(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());
        }
    }

}