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.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class DD {

	static class Trie {

		static class Node {

			Node left, right; // 0, 1
			int child;

			Node() {
			}
			
			public String toString (){
				return left + " " + right + " " + child;
			}
		}

		Node root;

		Trie() {
			root = new Node();
		}

		void insert(int x) {
			Node cur = root;
			for (int i = 30; i >= 0; i--) {
				long bit = x & (1L << i);
				if (bit == 0) {
					if (cur.left == null)
						cur.left = new Node();
					cur = cur.left;
				} else {
					if (cur.right == null)
						cur.right = new Node();
					cur = cur.right;
				}
				cur.child++;
			}
		}

		int search(int x) {
			Node cur = root;
			int res = 0, i;
			for (i = 30; i >= 0; i--) {
				long bit = x & (1L << i);
				if (bit == 0) {
					if (cur.right == null) {
						cur = cur.left;
					} else {
						res |= (1 << i);
						cur = cur.right;
					}
				} else {
					if (cur.left == null) {
						cur = cur.right;
					} else {
						res |= (1 << i);
						cur = cur.left;
					}
				}
			}
			return res;
		}

		void remove(int x) {
			remove(30, x, root);
		}

		void remove(int i, int x, Node node) {
			if (node == null)
				return;
			if ((x & (1L << i)) == 0) {
				remove(i - 1, x, node.left);
				if (node.left != null && node.left.child <= 1)
					node.left = null;
				else if(node.left != null && node.left.child > 1)
					node.left.child--;
					
			} else {
				remove(i - 1, x, node.right);
				if (node.right != null && node.right.child <= 1)
					node.right = null;
				else if(node.right != null && node.right.child > 1)
					node.right.child--;
			}
		}
	}

	public static void main(String[] args) throws IOException {
		MyScanner sc = new MyScanner(System.in);
		PrintWriter out = new PrintWriter(System.out);
		int n = sc.nextInt();
		Trie trie = new Trie();
		trie.insert(0);
		while (n-- > 0) {
			char c = sc.next().charAt(0);
			if (c == '+') {
				trie.insert(sc.nextInt());
			} else if (c == '-') {
				trie.remove(sc.nextInt());
			} else if (c == '?') {
				out.println(trie.search(sc.nextInt()));
			}
		}
		out.close();
	}

	static class MyScanner {

		BufferedReader br;
		StringTokenizer st;

		MyScanner(InputStream is) {
			br = new BufferedReader(new InputStreamReader(is));
		}

		String next() throws IOException {
			while (st == null || !st.hasMoreTokens())
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}

		int nextInt() throws IOException {
			return Integer.parseInt(next());
		}

		long nextLong() throws IOException {
			return Long.parseLong(next());
		}
	}
}
