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;
import java.util.StringTokenizer;

/**
 * Created by pallavi on 11/8/16.
 */
public class D706 {
    public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

        int q = Integer.parseInt(reader.readLine());
        Node r = new Node();
        update(r, 0, 30, 1);
        for (int i = 0; i < q; i++) {
            StringTokenizer tokenizer = new StringTokenizer(reader.readLine());
            String sw = tokenizer.nextToken();
            int j = Integer.parseInt(tokenizer.nextToken());
            switch (sw) {
                case "+":
                    update(r, j, 30, 1);
                    break;
                case "-":
                    update(r, j, 30, -1);
                    break;
                case "?":
                    System.out.println(xor(r, j, 30));
            }
        }
    }

    private static int xor(Node r, int i, int l) {
        if (l == -1) return 0;
        if ((i & (1<<l)) == 0) {
            if (r.left != null) {
                return (1<<l) + xor(r.left, i, --l);
            }
            else if (r.right != null) return xor(r.right, i, --l);
        } else {
            if (r.right != null) {
                return (1<<l) + xor(r.right, i, --l);
            }
            else if (r.left != null) return xor(r.left, i, --l);
        }
        return 0;
    }

    private static void update(Node r, int i, int l, int k) {
        if (l == -1) {
            r.count += k;
            return;
        }
        Node n;
        if ((i & (1<<l)) == 0) {
            n = r.getRight();
        } else {
            n = r.getLeft();
        }
        update(n, i, --l, k);
        if (n.count == 0 && n.left == null && n.right == null) {
            if (n == r.left) r.left = null;
            else r.right = null;
        }
    }

    static class Node {
        Node left, right;
        int count;

        public Node getLeft() {
            if (left == null) left = new Node();
            return left;
        }

        public Node getRight() {
            if (right == null) right = new Node();
            return right;
        }
    }
}
