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.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author MottoX
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskD solver = new TaskD();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskD {
        public void solve(int testNumber, InputReader in, PrintWriter out) {
            XorTrie trie = new XorTrie(200000 * 32, 2, '0');
            trie.insert(0);
            int q = in.nextInt();
            for (int i = 0; i < q; i++) {
                String op = in.next();
                int x = in.nextInt();
                if (op.equals("+")) {
                    trie.insert(x);
                } else if (op.equals("-")) {
                    trie.remove(x);
                } else {
                    out.println(trie.maxXor(x));
                }
            }
        }

        class XorTrie extends Trie {
            public XorTrie(int size, int charSetSize, char base) {
                super(size, charSetSize, base);
            }

            private boolean exist(int node) {
                return flag[node] > 0;
            }

            public int maxXor(int x) {
                int cur = root;
                String s = String.format("%32s", Integer.toBinaryString(x)).replace(' ', '0');
                int ret = 0;
                for (int i = 0; i < s.length(); i++) {
                    int index = s.charAt(i) - BASE;
                    int bit = exist(child[cur][index ^ 1]) ? index ^ 1 : index;
                    cur = child[cur][bit];
                    ret = ret * 2 + bit;
                }
                return ret ^ x;
            }

            public void insert(String s) {
                int cur = root;
                for (int i = 0; i < s.length(); i++) {
                    int index = s.charAt(i) - BASE;
                    if (child[cur][index] == 0) {
                        child[cur][index] = newNode();
                    }
                    cur = child[cur][index];
                    flag[cur]++;
                }
            }

            public void remove(String s) {
                int cur = root;
                for (int i = 0; i < s.length(); i++) {
                    int index = s.charAt(i) - BASE;
                    if (child[cur][index] == 0) {
                        return;
                    }
                    cur = child[cur][index];
                    if (flag[cur] > 0) {
                        flag[cur]--;
                    }
                }
            }

        }

    }

    static class InputReader {
        private final BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream));
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

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

    }

    static class Trie {
        protected final char BASE;
        protected int root;
        protected int[][] child;
        protected int[] flag;
        protected int total;

        public Trie(int size, int charSetSize, char base) {
            child = new int[size][charSetSize];
            flag = new int[size];
            BASE = base;
            init();
        }

        public void init() {
            total = 0;
            root = newNode();
        }

        protected int newNode() {
            ++total;
            Arrays.fill(child[total], 0);
            flag[total] = 0;
            return total;
        }

        public void insert(String s) {
            int cur = root;
            for (int i = 0; i < s.length(); i++) {
                int index = s.charAt(i) - BASE;
                if (child[cur][index] == 0) {
                    child[cur][index] = newNode();
                }
                cur = child[cur][index];
            }
            flag[cur]++;
        }

        public void insert(int x) {
            String binaryString = String.format("%32s", Integer.toBinaryString(x)).replace(' ', '0');
            insert(binaryString);
        }

        public void remove(String s) {
            int cur = root;
            for (int i = 0; i < s.length(); i++) {
                int index = s.charAt(i) - BASE;
                if (child[cur][index] == 0) {
                    return;
                }
                cur = child[cur][index];
            }
            if (flag[cur] > 0) {
                flag[cur]--;
            }
        }

        public void remove(int x) {
            String binaryString = String.format("%32s", Integer.toBinaryString(x)).replace(' ', '0');
            remove(binaryString);
        }

    }
}

