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.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;


public class D {

	private static BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
	private static PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));
	
	private static final int MAX = 30;
	
	private static class Trie {
		public int val = -1;
		public int cnt = 0;
		public Trie[] children = new Trie[2];
		public void add(int n) {
			add(n, MAX);
		}
		public void remove(int n) {
			remove(n, MAX);
		}
		public int find(int n) {
			return find(n, MAX);
		}
		public void add(int n, int bitIdx) {
			if (bitIdx == -1) {
				val = n;
				++cnt;
			} else {
				int bit = (n & (1 << bitIdx)) == 0 ? 0 : 1;
				if (children[bit] == null)
					children[bit] = new Trie();
				children[bit].add(n, bitIdx - 1);
			}
		}
		public boolean remove(int n, int bitIdx) {
			if (bitIdx == -1) {
				if (--cnt == 0)
					return true;
			} else {
				int bit = (n & (1 << bitIdx)) == 0 ? 0 : 1;
				if (children[bit].remove(n, bitIdx - 1)) {
					children[bit] = null;
					if (children[1 - bit] == null)
						return true;
				}
			}
			return false;
		}
		public int find(int n, int bitIdx) {
			if (bitIdx == -1)
				return val;
			int bit = (n & (1 << bitIdx)) == 0 ? 0 : 1;
			if (children[bit] != null)
				return children[bit].find(n, bitIdx - 1);
			return children[1 - bit].find(n, bitIdx - 1);
		}
	}
	
	public static void main(String[] args) throws IOException {
		int q = Integer.parseInt(in.readLine());
		Trie t = new Trie();
		t.add(0);
		while (q-- > 0) {
			String s = in.readLine();
			char c = s.charAt(0);
			int x = Integer.parseInt(s.substring(2));
			if (c == '+') {
				t.add(x);
			} else if (c == '-') {
				t.remove(x);
			} else {
				int y = ~x;
				int ans = t.find(y);
				out.println(ans^x);
			}
		}
		out.flush();
	}

}
