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.PrintWriter;
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);

        int q = in.nextInt();
        T root = new T();
        root.update(0, 1);

        for (int i = 0; i < q; i++) {
            char ch = in.next().charAt(0);
            int n = in.nextInt();
            if (ch == '+') {
                root.update(n, 1);
            } else if (ch == '-') {
                root.update(n, -1);
            } else if (ch == '?') {
                out.println(root.get(n));
            }
        }
        out.flush();
    }

    static class T {
        T p0, p1;
        int cnt0, cnt1;

        T() {
            this.cnt0 = 0;
            this.cnt1 = 0;
        }

        void update(int x, int v) {
            T cur = this;
            for (int i = 30; i >= 0; i--) {
                if ((x & (1 << i)) > 0) {
                    cur.cnt1 += v;
                    if (cur.p1 == null)
                        cur.p1 = new T();
                    cur = cur.p1;
                } else {
                    cur.cnt0 += v;
                    if (cur.p0 == null)
                        cur.p0 = new T();
                    cur = cur.p0;
                }
            }
        }

        int get(int x) {
            T cur = this;
            int res = 0;
            for (int i = 30; i >= 0; i--) {
                if ((x & (1 << i)) > 0) {
                    if (cur.cnt0 > 0) {
                        res += (1 << i);
                        cur = cur.p0;
                    } else
                        cur = cur.p1;
                } else {
                    if (cur.cnt1 > 0) {
                        res += (1 << i);
                        cur = cur.p1;
                    } else
                        cur = cur.p0;
                }
            }
            return res;
        }
    }
}
