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.ArrayList;
import java.util.Scanner;


public class Main {
    
    private static final int MAX_R = 2;
    private static class Node {
        Node[] next = new Node[MAX_R];
        int val = -1;
        int cnt = 0;
    }
    
    Node bapak;
    
    
    public void insertOrDelete(int val, boolean isInsert) {
        ArrayList<Integer> arr = new ArrayList<Integer>();
        int temp = val;
        while (temp != 0) {
            arr.add(temp % 2);
            temp /= 2;
        }
        while (arr.size() != 32) {
            arr.add(0);
        }
        bapak = insertOrDelete(bapak, arr, arr.size() - 1, val, isInsert);
    }
    private Node insertOrDelete(Node root, ArrayList<Integer> arr, int idx, int val, boolean isInsert) {
        if (root == null) {
            root = new Node();
        }
        if (idx == -1) {
        	if (isInsert) {
        		root.cnt++;
                root.val = val;
                //System.out.println("Inserted " + root.val);
                return root;
        	}
        	else {
        		root.cnt--;
        		if (root.cnt == 0) {
        			return null;
        		}
        		return root;
        	}
        }
        int nextIdx = arr.get(idx);
        root.next[nextIdx] = insertOrDelete(root.next[nextIdx], arr, idx - 1, val, isInsert);
        if (isInsert) 
        	return root;
        else {
        	if (root.next[nextIdx] == null && root.next[1 - nextIdx] == null && root.cnt == 0) {
        		return null;
        	}
        	else {
        		return root;
        	}
        }
    }
    public int search(int val) {
        ArrayList<Integer> arr = new ArrayList<Integer>();
        int temp = val;
        while (temp != 0) {
            arr.add(temp % 2);
            temp /= 2;
        }
        while (arr.size() != 32) {
            arr.add(0);
        }
        return search(bapak, val, arr, arr.size() - 1);
    }
    private int search(Node root, int val, ArrayList<Integer> arr, int idx) {
        if (root == null) {
            return val;
        }

//        System.out.println("sini  " + root.val + " " + val);
        if (idx == -1) {
            //return root.val != -1 ? root.val ^ val : val;

        	return root.val ^ val;
        }
        int nextIdx = arr.get(idx);
        if (root.next[nextIdx] == null && root.next[1 - nextIdx] == null) {
        	System.out.println(root.val + " " + root.cnt);
        	return root.val ^ val;
        }
        else {
            Node temp = root.next[1 - nextIdx] == null ? root.next[nextIdx] : root.next[1 - nextIdx];
            return search(temp, val, arr, idx - 1);
        }
    }
    public static void main(String[] args) {

        Main m = new Main();
        Scanner sc = new Scanner(System.in);
        String symbol; 
        int TC = sc.nextInt(), temp;
        for (int t = 0; t < TC; t++) {
        	symbol = sc.next();
        	temp = sc.nextInt();
        	if (symbol.charAt(0) == '+' || symbol.charAt(0) == '-') {
        		boolean isInsert = symbol.charAt(0) == '+';
        		m.insertOrDelete(temp,  isInsert);
        	}
        	else {
        		int ans = m.search(temp);
        		if (ans < temp) {
        			ans = temp;
        		}
        		System.out.println(ans);
        	}
        }
    }
}
