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.InputStreamReader;
import java.io.Reader;
import java.util.*;

public class D {
    public static void main(String[] args) {
//        Scanner sc = new Scanner(System.in);
        FastScanner sc = new FastScanner();

        root = new Trie();
        int numQueries = sc.nextInt();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < numQueries; i++) {
            char type = sc.next().charAt(0);
            long x = sc.nextLong();
            if (type == '+') {
                add(x);
            } else if (type == '-') {
                remove(x);
            } else { // '?'
                long max = x;
                max = Math.max(max, getMax(root, x, 31));
                System.out.println(max);
//                sb.append(max).append('\n');
            }
        }

//        System.out.print(sb);
    }

    static Map<Long, Integer> multiset = new HashMap<>();

    static void add(long val) {
        Integer count = multiset.get(val);
        if (count == null) {
            multiset.put(val, 1);
            insert(root, val, 31);
        } else {
            multiset.put(val, count + 1);
        }
    }

    static void remove(long val) {
        Integer count = multiset.get(val);
        if (count != null) {
            if (count == 1) {
                multiset.remove(val);
                remove(root, val, 31);
            } else {
                multiset.put(val, count - 1);
            }
        }
    }

    static Trie root;

    static class Trie {
        Trie zero, one;
        long val;
    }

    static long getMax(Trie node, long val, int level) {
        if (node == null) return val;
        if (level == -1) {
            return node.val ^ val;
        }
        if ((val & (1 << level)) == 0) {
            long ret = getMax(node.one, val, level - 1);
            if (ret <= val) {
                ret = getMax(node.zero, val, level - 1);
            }
            return ret;
        } else {
            long ret = getMax(node.zero, val, level - 1);
            if (ret <= val) {
                ret = getMax(node.one, val, level - 1);
            }
            return ret;
        }
    }

    static Trie remove(Trie node, long val, int level) {
        if (level == -1) {
            return null;
        }
        if (node == null) return null;
        if ((val & (1 << level)) == 0) {
            node.zero = remove(node.zero, val, level - 1);
        } else {
            node.one = remove(node.one, val, level - 1);
        }
        if (node.zero == null && node.one == null) return null;
        return node;
    }

    static Trie insert(Trie node, long val, int level) {
        if (node == null) node = new Trie();
        if (level == -1) {
            node.val = val;
            return node;
        }
        if ((val & (1 << level)) == 0) {
            node.zero = insert(node.zero, val, level - 1);
        } else {
            node.one = insert(node.one, val, level - 1);
        }
        return node;
    }

    static void shuffle(int[] arr) {
        Random rng = new Random();
        int length = arr.length;
        for (int idx = 0; idx < arr.length; idx++) {
            int toSwap = idx + rng.nextInt(length-idx);
            int tmp = arr[idx];
            arr[idx] = arr[toSwap];
            arr[toSwap] = tmp;
        }
    }

    public static class FastScanner {
        BufferedReader br;
        StringTokenizer st;
        public FastScanner(Reader in) {
            br = new BufferedReader(in);
        }
        public FastScanner() {
            this(new InputStreamReader(System.in));
        }
        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }
        int nextInt() {
            return Integer.parseInt(next());
        }
        long nextLong() {
            return Long.parseLong(next());
        }
        double nextDouble() {
            return Double.parseDouble(next());
        }
        String readNextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
        int[] readIntArray(int n) {
            int[] a = new int[n];
            for (int idx = 0; idx < n; idx++) {
                a[idx] = nextInt();
            }
            return a;
        }
        long[] readLongArray(int n) {
            long[] a = new long[n];
            for (int idx = 0; idx < n; idx++) {
                a[idx] = nextLong();
            }
            return a;
        }
    }
}
