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.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.StringTokenizer;

public class D {
    public static class DS {
        public int count;
        public int val;
        public DS left, right;

        public DS() {
            this.count = 0;
            this.val = - 1;
        }

        public void ensureLeft() {
            if (left == null) {
                left = new DS();
            }
        }

        public void ensureRight() {
            if (right == null) {
                right = new DS();
            }
        }

        public void add(int x, int d) {
            count += 1;
            if (d >= 0) {
                if ((x & (1 << d)) > 0) {
                    ensureLeft();
                    left.add(x, d - 1);
                } else {
                    ensureRight();
                    right.add(x, d - 1);
                }
            } else if (d == -1) {
                val = x;
            }
        }

        public void remove(int x, int d) {
            count -= 1;
            if (d >= 0) {
                if ((x & (1 << d)) > 0) {
                    ensureLeft();
                    left.remove(x, d - 1);
                } else {
                    ensureRight();
                    right.remove(x, d - 1);
                }
            }
        }

        public boolean hasRight() {
            if (right == null) {
                return false;
            }
            return right.count > 0;
        }

        public boolean hasLeft() {
            if (left == null) {
                return false;
            }
            return left.count > 0;
        }

        public int maxXor(int x, int d) {
            if (d == -1) {
                return (x ^ val);
            }
//            if (d == 3) {
//                System.out.println("dvg");
//            }
            boolean ourBit = (x & (1 << d)) > 0;
            if (ourBit && hasRight()) {
                return (1 << d) | right.maxXor(x, d - 1);
            }
            if (!ourBit && hasLeft()) {
                return (1 << d) | left.maxXor(x, d - 1);
            }
            if (ourBit && hasLeft()) {
                return left.maxXor(x, d - 1);
            }
            if (!ourBit && hasRight()) {
                return right.maxXor(x, d - 1);
            }
            return 0;
        }

        public int maxXor(int x) {
            return Math.max(x, maxXor(x, 30));
        }

        public void add(int x) {
            add(x, 30);
        }

        public void remove(int x) {
            remove(x, 30);
        }
    }
    public static void main(String [] args) throws IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));
        int n = Integer.parseInt(in.readLine());
        DS ds = new DS();
        for (int i =0; i < n; i++) {
            String [] arg = in.readLine().split(" ");
            Integer val = Integer.parseInt(arg[1]);
            if (arg[0].equals("+")) {
                ds.add(val);
            } else if (arg[0].equals("-")) {
                ds.remove(val);
            } else if (arg[0].equals("?")){
                out.println(ds.maxXor(val));
            }
        }
        out.close();
    }
}
