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.InputStreamReader;

/**
 * Aug 11, 2016 | 5:31:43 PM
 * <pre>
 * <u>Description</u>
 *
 * </pre>
 * <p>
 * @author Essiennta Emmanuel (colourfulemmanuel@gmail.com)
 */
public class ProblemD {

    Node head = new Node();

    class Node {

        Node left;
        Node right;
        int cnt;
    }

    void solve(char[] op, int[] v) {
        for (int i = 0; i < op.length; i++) {
            switch (op[i]) {
                case '+':
                    add(v[i]);
                    break;
                case '-':
                    remove(v[i]);
                    break;
                case '?':
                    System.out.println(best(v[i]));
                    break;
            }
        }
    }

    void add(int x) {
//        System.out.println("adding " + x);
        Node parent = head;
        for (int depth = 29; depth >= 0; depth--) {
            if ((x & 1 << depth) != 0) {
                // 1-right
                if (parent.right == null)
                    parent.right = new Node();
                parent = parent.right;
            } else {
                // 0-left
                if (parent.left == null)
                    parent.left = new Node();
                parent = parent.left;
            }
            parent.cnt++;
        }
    }

    void remove(int x) {
//        System.out.println("removing " + x);
        Node parent = head;
        for (int depth = 29; depth >= 0; depth--) {
            if ((x & 1 << depth) != 0) {
                // 1-right
                Node right = parent.right;
                if (right.cnt == 1)
                    parent.right = null;
                parent = right;
            } else {
                // 0-left
                Node left = parent.left;
                if (left.cnt == 1)
                    parent.left = null;
                parent = left;
            }
            parent.cnt--;
        }
    }

    int best(int x) {
//        System.out.println("best for " + x);
        int ans = 0;
        if (head.left == null && head.right == null)
            return x;
        Node curr = head;
        for (int depth = 29; depth >= 0; depth--) {
            if ((x & 1 << depth) != 0) {
                // 1-right
                if (curr.left != null) {
                    ans |= 1 << depth;
                    curr = curr.left;
                } else {
                    curr = curr.right;
                }
            } else {
                // 0-left
                if (curr.right != null) {
                    ans |= 1 << depth;
                    curr = curr.right;
                } else {
                    curr = curr.left;
                }
            }
        }
        return Math.max(ans, x);
    }

    public static void main(String[] args) throws IOException {
        try (BufferedReader in = new BufferedReader(new InputStreamReader(System.in))) {
            char[] op = new char[Integer.parseInt(in.readLine())];
            int[] v = new int[op.length];
            for (int i = 0; i < op.length; i++) {
                String[] tokens = in.readLine().split(" ");
                op[i] = tokens[0].charAt(0);
                v[i] = Integer.parseInt(tokens[1]);
            }
            new ProblemD().solve(op, v);
        }
    }
}
