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.Scanner;
 
public class Main
{	
	private static class TrieNode
	{
		public TrieNode left , right , parent;
		public int cnt;
		
		public TrieNode() { }
	}
	
	public static void main(String[] args)
	{
		Scanner scan = new Scanner(System.in);
		TrieNode root = new TrieNode();
		insert(root , 0);
		int q;
		q = scan.nextInt();
		while (q > 0)
		{	
			char ch;
			int value;
			
			ch = scan.next().charAt(0);
			value = scan.nextInt();
			
			if (ch == '+')
				insert(root , value);
			else if (ch == '-')
				erase(root , value);
			else
				System.out.println(getMax(root , value));
				
			q --;
		}
	}
	
	private static int getMax(TrieNode root , int value)
	{
		int ans = 0;
		for (int i = 31;i >= 0;i --)
		{
			int index = (value & (1 << i)) != 0 ? 1 : 0;
			if (index == 0)
			{
				if (root.right != null)
				{
					ans = ans | (1 << i);
					root = root.right;
				}
				else
					root = root.left;
			}
			else
			{
				if (root.left != null)
				{
					ans = ans | (1 << i);
					root = root.left;
				}
				else
					root = root.right;
			}
		}
		return ans;
	}
	
	// value inserted into trie
	private static void insert(TrieNode root , int value)
	{
		for (int i = 31;i >= 0;i --)
		{
			TrieNode parent = root;
			int index = (value & (1 << i)) != 0 ? 1 : 0;
			if (index == 0)
			{
				if (root.left == null)
					root.left = new TrieNode();
				root = root.left;
			}
			else
			{
				if (root.right == null)
					root.right = new TrieNode();
				root = root.right;
			}
			root.parent = parent;
		}
		root.cnt ++;
	}
	
	// erase value from trie
	private static void erase(TrieNode root , int value)
	{
		for (int i = 31;i >= 0;i --)
		{
			int index = ((value & (1 << i)) != 0) ? 1 : 0;
			if (index == 0)
				root = root.left;
			else
				root = root.right;
		}
		root.cnt --;
		
		if (root.cnt == 0)
		{
			if (root.left == null && root.right == null)
			{
				while (root.parent != null && root.cnt == 0 && (root.left == null && root.right == null))
				{
					TrieNode parent = root.parent;
					if (parent.left == root)
						parent.left = null;
					else
						parent.right = null;
					root = parent;
				}
			}
		}
	}	
	
}
