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.StringTokenizer;


public class Main {

    public static void main(String[] args) throws IOException {
        Scanner sc = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        SuffixTrie st = new SuffixTrie();
        st.addNum(0);
        int q = sc.nextInt();
        while (q-- > 0) {
            char op = sc.nextChar();
            int x = sc.nextInt();
            switch (op) {
                case '+':
                    st.addNum(x);
                    break;
                case '-':
                    st.removeNum(x);
                    break;
                default:
                    out.println(st.getMax(x));
            }
        }
        out.flush();
        out.close();
    }

    static class SuffixTrie {
        Node root;

        SuffixTrie() {
            root = new Node();
        }

        void addNum(int x) {
            Node cur = root;
            root.val++;
            for (int i = 31; i >= 0; i--) {
                int idx = (x & (1 << i)) == 0 ? 0 : 1;
                if (cur.next[idx] == null) cur.next[idx] = new Node();
                cur.next[idx].val++;
                cur = cur.next[idx];
            }
        }

        void removeNum(int x) {
            Node cur = root;
            cur.val--;
            for (int i = 31; i >= 0; i--) {
                int idx = (x & (1 << i)) == 0 ? 0 : 1;
                cur.next[idx].val--;
                cur = cur.next[idx];
            }

        }

        int getMax(int x) {
            int ans = 0;
            Node cur = root;
            for (int i = 31; i >= 0; i--) {
                int need = (x & (1 << i)) == 0 ? 1 : 0;

                if (cur.next[need] == null || cur.next[need].val == 0) {
                    cur = cur.next[1 - need];
                } else {
                    ans |= (1 << i);
                    cur = cur.next[need];
                }

            }
            return ans;
        }

        static class Node {
            Node[] next;
            int val;

            Node() {
                next = new Node[2];
            }
        }
    }

    static class Scanner {
        StringTokenizer st;
        BufferedReader br;

        public Scanner(InputStream system) {
            br = new BufferedReader(new InputStreamReader(system));
        }

        public Scanner(String file) throws Exception {
            br = new BufferedReader(new FileReader(file));
        }

        public String next() throws IOException {
            while (st == null || !st.hasMoreTokens()) st = new StringTokenizer(br.readLine());
            return st.nextToken();
        }

        public String nextLine() throws IOException {
            return br.readLine();
        }

        public int nextInt() throws IOException {
            return Integer.parseInt(next());
        }

        public double nextDouble() throws IOException {
            return Double.parseDouble(next());
        }

        public char nextChar() throws IOException {
            return next().charAt(0);
        }

        public Long nextLong() throws IOException {
            return Long.parseLong(next());
        }

        public boolean ready() throws IOException {
            return br.ready();
        }

        public void waitForInput() throws InterruptedException {
            Thread.sleep(3000);
        }
    }
}