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>.
// CodeForces Round 367 -- slowe

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;


public class D367 {
	public static void main(String[] args) throws Exception {
		FastScanner in = new FastScanner();
		PrintWriter pw = new PrintWriter(System.out);
		
		Tree t = new Tree();
		t.add(0);
		
		int q = in.nextInt();
		while(q-->0) {
			char op = in.next().charAt(0);
			if(op == '+')
				t.add(in.nextInt());
			else if(op == '-')
				t.remove(in.nextInt());
			else pw.println(t.xor(in.nextInt()));
		}
		
		pw.flush();
		pw.close();
	}
	
	static class Node {
		int count, subTreeCount;
		Node[] children;
		
		public Node() {
			children = new Node[2];
		}
		
		void add(int x, int k) {
			subTreeCount++;
			if(k == -1)
				count++;
			else {
				int bit = (x >> k)%2;
				if(children[bit] == null)
					children[bit] = new Node();
				children[bit].add(x, k-1);
			}
		}
		
		void remove(int x, int k) {
			subTreeCount--;
			if(k == -1)
				count--;
			else {
				int bit = (x >> k)%2;
				children[bit].remove(x, k-1);
				if(children[bit].subTreeCount == 0)
					children[bit] = null;
			}
		}
		
		int xor(int x, int k, int xor) {
			if(k == -1)
				return xor;
			
			int bit = (x >> k)%2;
			
			if(children[0] == null) {
				xor <<= 1;
				xor += 1-bit;
				return children[1].xor(x, k-1, xor);
			}
			if(children[1] == null) {
				xor <<= 1;
				xor += bit;
				return children[0].xor(x, k-1, xor);
			}
			
			xor <<= 1;
			xor++;
			return children[1-bit].xor(x, k-1, xor);
		}
	}
	
	static class Tree {
		Node root = new Node();
		
		void add(int x) {
			root.add(x, 31);
		}
		
		void remove(int x) {
			root.remove(x, 31);
		}
		
		int xor(int x) {
			return root.xor(x, 31, 0);
		}
	}
	
	static class FastScanner {
		BufferedReader br;
		StringTokenizer st;
		public FastScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
			st = new StringTokenizer("");
		}
		
		String next() throws Exception {
			while(!st.hasMoreTokens())
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}
		
		int nextInt() throws Exception {
			return Integer.parseInt(next());
		}
	}
}
