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

public class C {
	public static void main(String[] args) throws IOException {
		try (FastScanner s = new FastScanner(); PrintWriter pw = new PrintWriter(System.out);) {
			final int q = s.nextInt();
			
			Node root = new Node();
			
			Node current = root;
			for (int i = 31; i >= 0; --i) {
				Node node = current.getOrCreateAt(0);
				node.c++;
				current = node;
			}
			
			for (int j = 0; j < q; ++j) {
				String type = s.next();
				int x = s.nextInt();
				switch (type) {
				case "+":
					current = root;
					for (int i = 31; i >= 0; --i) {
						Node node = current.getOrCreateAt((x >> i) & 1);
						node.c++;
						current = node;
					}
		            break;
				case "-":
					current = root;
					for (int i = 31; i >= 0; --i) {
						Node node = current.getAt((x >> i) & 1);
						node.c--;
						current = node;
					}
		            break;
				case "?":
					int res = 0;
					current = root;
					for (int i = 31; i >= 0; --i) {
						Node node = current.getAt(1 - ((x >> i) & 1));
						if (node != null && node.c > 0) {
							res |= (1 << i);
							current = node;
						} else {
							current = current.getAt(((x >> i) & 1));
						}
					}
					pw.println(res);
					break;
				}
			}
		}
	}

	private static class Node {
		private final Node[] nodes = new Node[2];
		private int c;
		
		Node getAt(int i) {
			return nodes[i];
		}
		
		Node getOrCreateAt(int i) {
			if (nodes[i] == null) {
				nodes[i] = new Node();
			}
			return nodes[i];
		}
	}

	private static class FastScanner implements Closeable {
		private final BufferedReader reader;
		private String[] tokens;
		private int next;
		
		FastScanner() {
			reader = new BufferedReader(new InputStreamReader(System.in));
		}
		
		String next() throws IOException {
			if (tokens == null || tokens.length == next) {
				tokens = reader.readLine().split(" ");
				next = 0;
			}
			return tokens[next++];
		}
		
		int nextInt() throws IOException {
			return Integer.parseInt(next());
		}

		@Override
		public void close() throws IOException {
			reader.close();
		}
	}
}
