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.BufferedInputStream;
import java.util.Scanner;

public class CTrees {

    static Node root = new Node();

    public static void main(String[] args) {
        final Scanner scanner = new Scanner(new BufferedInputStream(System.in));
        int n = scanner.nextInt();
        add(0);
        for (int i = 0; i < n; i++) {
            char type = scanner.next().charAt(0);
            int value = scanner.nextInt();
            switch (type) {
                case '+': {add(value); break;}
                case '-': {remove(value); break;}
                default: {get(value); break;}
            }
        }
    }
    private static class Node {
        int subNodes = 0;
        Node[] childs = new Node[2];
    }

    private static void get(int value) {
        Node iterator = root;
        int result = 0;
        for (int i = 30; i >= 0; i--) {
            int mask = (value & (1 << i)) >> i;
            if (iterator.childs[mask ^ 1] != null) {
                result += (1 << i);
                iterator = iterator.childs[mask ^ 1];
            } else {
                iterator = iterator.childs[mask];
            }
        }
        System.out.println(result);
    }

    private static void remove(int value) {
        Node iterator = root;
        iterator.subNodes--;
        for (int i = 30; i >= 0; i--) {
            int mask = (value & (1 << i)) >> i;
            iterator.childs[mask].subNodes--;
            if (iterator.childs[mask].subNodes == 0) {
                iterator.childs[mask] = null;
                break;
            }
            iterator = iterator.childs[mask];
        }
    }

    private static void add(int value) {
        Node iterator = root;
        for (int i = 30; i >= 0; i--) {
            int mask = (value & (1 << i)) >> i;
            iterator.subNodes++;
            if (iterator.childs[mask] == null) {
                iterator.childs[mask] = new Node();
            }
            iterator = iterator.childs[mask];
        }
        iterator.subNodes++;
    }

}
