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.*;

/**
 * Created by chao on 16/12/14.
 */
public class A {

    public static void main(String[] args) throws IOException {
        PrintWriter pw = new PrintWriter(new OutputStreamWriter(System.out));
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        Node root = new Node(0);
        root.useTime = 1;
        root.endTime = 1;

        int q = Integer.parseInt(br.readLine());
        while(q-- > 0) {
            String[] nums = br.readLine().split(" ");
            int val = Integer.parseInt(nums[1]);
            if ("+".equals(nums[0])) {
                add(root, 0, val);
            } else if ("-".equals(nums[0])) {
                remove(root, 0, val);
            } else {
                pw.println(cal(root, 0, val));
            }
        }


        pw.flush();
        pw.close();
        br.close();

    }

    private static void add(Node nd, int depth, int x) {
        nd.useTime++;
        if (isLastBit(depth, x)) {
            nd.endTime++;
            return;
        }
        if (getBitVal(depth+1, x) == 0) {
            if (nd.left == null) {
                nd.left = new Node(nd.val);
            }
            add(nd.left, depth+1, x);
        } else {
            if (nd.right == null) {
                nd.right = new Node(nd.val | getBitVal(depth+1, x));
            }
            add(nd.right, depth+1, x);
        }

    }

    private static void remove(Node nd, int depth, int x) {
        nd.useTime--;
        if (isLastBit(depth, x)) {
            nd.endTime--;
            return;
        }
        if (getBitVal(depth+1, x) == 0) {
            remove(nd.left, depth+1, x);
        } else {
            remove(nd.right, depth+1, x);
        }
    }

    private static int cal(Node nd, int depth, int x) {
        int ans = 0;
        if (hasNode(nd.left) && hasNode(nd.right)) {
            if (getBitVal(depth+1, x) == 0) {
                ans = cal(nd.right, depth+1, x);
            } else {
                ans = cal(nd.left, depth+1, x);
            }

        } else if (hasNode(nd.left)) {
            ans = cal(nd.left, depth+1, x);
        } else if (hasNode(nd.right)) {
            ans = cal(nd.right, depth+1, x);
        }
        if (nd.endTime > 0) {
            ans = Math.max(ans, nd.val ^ x);
        }
        return ans;
    }

    private static boolean hasNode(Node nd) {
        return (nd != null && nd.useTime != 0);
    }

    private static int getBitVal(int depth, int x) {
        return ((1<<(30-depth))&x);
    }

    private static boolean isLastBit(int depth, int x) {
        if (depth >= 30) return true;
        // end up with zero from depth+1
        return  ((((1<<(30-depth))-1) & x ) == 0);
    }


}

class Node{
    Node left, right;
    int useTime, endTime;
    int val;

    public Node(int val) {
        this.val = val;
    }
}

