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.Arrays;

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

    static Node root;
    static int[] last = new int[31];

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

        init();

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

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

    }

    private static void init() {
        for (int i = 0; i <= 30; i++) {
            last[i] = (1<<(31-i)) - 1;
        }
    }

    private static void add(Node nd, int depth, int x) {
        nd.useTime++;
        if (isAllZero(depth+1, x)) {
            nd.endTime++;
            return;
        }
        if (isZero(depth+1, x)) {
            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));
            add(nd.right, depth+1, x);
        }

    }

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

    }

    private static boolean isAllZero(int depth, int x) {
        // 1. last bit
        // 2. tailing zero
        if (depth > 30) return true;
        if ((x & last[depth]) == 0) return true;
        return false;
    }

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

    private static boolean isZero(int depth, int x) {
        // this bis is zero
        return ((1<<(30-depth)) & x) == 0;
    }

    private static int cal(Node nd, int depth, int x) {
        int val = (nd.val ^ x);
        if (isNull(nd.left) && isNull(nd.right))
            return val;
        else {
            int val2 = 0;
            if (isNull(nd.left)) {
                val2 = cal(nd.right, depth + 1, x);
            } else if (isNull(nd.right)) {
                val2 = cal(nd.left, depth + 1, x);
            } else {
                if ((x^nd.left.val) > (x^nd.right.val)) {
                    val2 = cal(nd.left, depth+1, x);
                } else {
                    val2 = cal(nd.right, depth+1, x);
                }
            }
            if (nd.endTime > 0) {
                val2 = Math.max(val, val2);
            }
            return val2;
        }
        // 1. 如果是最后层,直接return
        // 2. 如果没有儿子,直接return
        // 3. 如果只有一个儿子, cal 儿子
        // 4. 如果有2个儿子, cal 其中一个儿子
        // 5. 如果本身是end, return Max(3-4, 本身)
    }

    private static boolean isNull(Node nd) {
        if (nd == null || nd.useTime == 0) return true;
        return false;
    }

}


class Node {
    int endTime;
    int useTime;
    int val;
    Node left;
    Node right;
    public Node(int val, int endTime, int useTime) {
        this.val = val;
        this.endTime = endTime;
        this.useTime = useTime;
    }
    public Node(int val) {
        this.val = val;
    }

}
