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.util.*;
import java.io.*;

public class P706D {

  private static class Node {
    private Node left;
    private Node right;
    private Node parent;
    private int val;
    private int cnt;
  }

  private static void solve() {
    int MAX = 30;
    int n = nextInt();

    Node root = new Node();

    for (int i = 0; i < n; i++) {
      char type = next().toCharArray()[0];
      int num = nextInt();

      if (type == '+') {
        Node tmp = root;
        for (int j = MAX; j >= 0; j--) {
          if ((num & (1 << j)) != 0) {
            if (tmp.right == null) {
              tmp.right = new Node();
              tmp.right.parent = tmp;
            }
            tmp = tmp.right;
          } else {
            if (tmp.left == null) {
              tmp.left = new Node();
              tmp.left.parent = tmp;
            }
            tmp = tmp.left;
          }
        }

        tmp.val = num;
        tmp.cnt++;
      } else if (type == '-') {
        Node tmp = root;
        for (int j = MAX; j >= 0; j--) {
          if ((num & (1 << j)) != 0) {
            tmp = tmp.right;
          } else {
            tmp = tmp.left;
          }
        }

        tmp.cnt--;

        if (tmp.cnt == 0) {
          while (tmp != root) {
            if (tmp.parent.left == tmp) {
              tmp.parent.left = null;
              if (tmp.parent.right != null) {
                break;
              }
              tmp = tmp.parent;
            } else {
              tmp.parent.right = null;
              if (tmp.parent.left != null) {
                break;
              }
              tmp = tmp.parent;
            }
          }
        }
      } else {
        Node tmp = root;
        if (root.left == null && root.right == null) {
          out.println(num);
        } else {
          for (int j = MAX; j >= 0; j--) {
            if ((num & (1 << j)) != 0) {
              if (tmp.left != null) {
                tmp = tmp.left;
              } else {
                tmp = tmp.right;
              }
            } else {
              if (tmp.right != null) {
                tmp = tmp.right;
              } else {
                tmp = tmp.left;
              }
            }
          }
          out.println(Math.max(num, tmp.val ^ num));
        }
      }
    }
  }

  private static void run() {
    br = new BufferedReader(new InputStreamReader(System.in));
    out = new PrintWriter(System.out);

    solve();

    out.close();
  }

  private static StringTokenizer st;
  private static BufferedReader br;
  private static PrintWriter out;

  private static String next() {
    while (st == null || !st.hasMoreElements()) {
      String s;
      try {
        s = br.readLine();
      } catch (IOException e) {
        return null;
      }
      st = new StringTokenizer(s);
    }
    return st.nextToken();
  }

  private static int nextInt() {
    return Integer.parseInt(next());
  }

  private static long nextLong() {
    return Long.parseLong(next());
  }

  public static void main(String[] args) {
    run();
  }
}