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.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.PriorityQueue;
import java.util.StringTokenizer;
import java.util.TreeMap;

public class A {
	


	public static void main(String[] args) throws Exception {
		Scanner sc=new Scanner(System.in);
		PrintWriter pw=new PrintWriter(System.out);
		trie trie=new trie();
		trie.insert(0);
		int q=sc.nextInt();
		
		while(q-->0)
		{
			char c=sc.next().charAt(0);
			int x=sc.nextInt();
			if(c=='+')
				trie.insert(x);
			else if(c=='-')
				trie.remove(x);
			else
				pw.println(trie.query(x, 29, trie.root));
		}
		pw.close();
		

		
	}
	static class trie
	{
		node root;
		trie()
		{
			root=new node(0);
		}
		void insert(int x)
		{
			insert(x,29,root);
		}
		void remove(int x)
		{
			remove(x,29,root);
		}
		void remove(int x,int bit,node node)
		{
			if(bit==-1)
				return;
			if((x& 1<<bit) !=0)
			{	
				node.one.cnt--;
				remove(x,bit-1,node.one);
			}	
			else
			{	
				node.zro.cnt--;
				remove(x,bit-1,node.zro);
			}	
				
		}
		void insert(int x,int bit,node node)
		{
			if(bit==-1)
				return;
			if((x& 1<<bit) !=0)
			{	
				node.addEdge(1);
				insert(x,bit-1,node.one);
			}	
			else
			{	
				node.addEdge(0);
				insert(x,bit-1,node.zro);
			}	
				
		}
		public int query(int x,int bit,node node)
		{
			
			if(bit==-1)
				return 0;
			if((x & 1<<bit) ==0)
			{
				if(node.hasChild(1))
					return (1<<bit) + query(x,bit-1,node.one);
				return query(x,bit-1,node.zro);
			}
			if(node.hasChild(0))
				return (1<<bit) + query(x,bit-1,node.zro);
			return query(x,bit-1,node.one);
		}
	}
	static class node
	{
		int cnt;
		node one,zro;
		node(int x)
		{
			cnt=x;
		}
		public boolean hasChild(int type)
		{
			if(type==1)
			{
				return one!=null && one.cnt>0; 
			}
			return zro!=null && zro.cnt>0;
		}
		void addEdge(int type)
		{
			if(type==1)
			{
				if(one==null)
					one=new node(1);
				else
					one.cnt++;
			}
			else
			{
				if(zro==null)
					zro=new node(1);
				else
					zro.cnt++;
			}
		}
	}

	
	
	static class Scanner
	{
		StringTokenizer st;
		BufferedReader br;

		public Scanner(InputStream s) {
			br = new BufferedReader(new InputStreamReader(s));
		}

		public Scanner(FileReader fileReader) {
			br = new BufferedReader(fileReader);
		}

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

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

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

		public String nextLine() throws IOException {
			return br.readLine();
		}

		public boolean ready() throws IOException {
			return br.ready();
		}
	}
}