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.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.*;

/**
 * @author Mubtasim Shahriar
 */

public class VasilyMultiset {

    public static void main(String[] args) {

        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader sc = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        Solver solver = new Solver();
//		int t = sc.nextInt();
        int t = 1;
        while (t-- != 0) {
            solver.solve(sc, out);
        }
        out.close();

    }

    static class Solver {
        public void solve(InputReader sc, PrintWriter out) {
            Trie trie = new Trie();
            StringBuilder sb = new StringBuilder();
            for(int i = 0; i < 31; i++) sb.append('0');
            trie.insert(sb.toString());
            HashMap<Integer,Integer> hm = new HashMap<>();
            hm.put(0,1);
            int n = sc.nextInt();
            for(int i = 0; i < n; i++) {
                String sign = sc.next();
                sb = new StringBuilder();
                if(sign.equals("+")) {
                    int x = sc.nextInt();
                    boolean add = add(hm,x);
                    if(!add) continue;
                    String now = getString(x);
                    trie.insert(now);
                } else if(sign.equals("-")) {
                    int x = sc.nextInt();
                    boolean rem = rem(hm,x);
                    if(!rem) continue;
                    String now = getString(x);
                    trie.delete(now);
                } else {
                    int x = sc.nextInt();
                    String now = getString(x);
                    int big = trie.getBig(now);
                    out.println(big);
                }
            }
        }

        private String getString(int x) {
            int now = 1;
            StringBuilder sb = new StringBuilder();
            sb.append((now&x)!=0 ? 1 : 0);
            for(int bit = 0; bit < 30; bit++) {
                now *= 2;
                sb.append((now&x)!=0 ? 1 : 0);
            }
            return sb.reverse().toString();
        }

        private boolean rem(HashMap<Integer, Integer> hm, int x) {
            boolean one = (int)hm.get(x)==1;
            if(one) {
                hm.remove(x);
            } else {
                hm.put(x,hm.get(x)-1);
            }
            return one;
        }

        private boolean add(HashMap<Integer, Integer> hm, int x) {
            boolean have = hm.containsKey(x);
            if(!have) {
                hm.put(x,1);
            } else {
                hm.put(x,hm.get(x)+1);
            }
            return !have;
        }
    }

    static class Trie {
        final TreeNode root;
        Trie() {
            root = new TreeNode();
        }
        void insert(String word) {
            TreeNode current = root;
            for(int i = 0; i < word.length(); i++) {
                int number = getN(word.charAt(i));
                TreeNode node = current.children[number];
                if(node==null) {
                    node = new TreeNode();
                    current.children[number] = node;
                }
                current = node;
            }
            current.endOfWord = true;
        }
        void delete(String word){
            delete(root,word,0);
        }
        boolean delete(TreeNode current, String word, int index) {
            if(index==word.length()) {
                if(!current.endOfWord) return false;
                current.endOfWord = false;
                return current.children[0] == null && current.children[1] == null;
            }
            int number = getN(word.charAt(index));
            TreeNode node = current.children[number];
            if(node==null) return false;
            boolean shouldDeleteCurrentNode = delete(node,word,index+1);
            if(shouldDeleteCurrentNode) {
                current.children[number] = null;
                return current.children[0] == null && current.children[1] == null;
            }
            return false;
        }

        private int getN(char charAt) {
            return charAt - '0';
        }

        public int getBig(String now) {
            int ret = 0;
            TreeNode current = root;
//            System.out.println(now);
            if(current==null) throw new RuntimeException();
            StringBuilder sb = new StringBuilder();
            for(int i = 0; i < now.length(); i++) {
                int number = getN(now.charAt(i));
                int prev = number;
                number ^= 1;
                TreeNode node = current.children[number];
                if(node==null) {
                    number ^= 1;
                    node = current.children[number];
                }
                sb.append(prev^number);
                current = node;
            }
            sb = sb.reverse();
            for(int i = 0; i < sb.length(); i++) {
                if(sb.charAt(i)=='1') ret |= (1<<i);
            }
            return ret;
        }
    }

    static class TreeNode {
        TreeNode[] children;
        boolean endOfWord;
        TreeNode(){
            children = new TreeNode[2];
            endOfWord = false;
        }
    }

    static void sort(int[] arr) {
        Random rand = new Random();
        int n = arr.length;
        for (int i = 0; i < n; i++) {
            int idx = rand.nextInt(n);
            if (idx == i) continue;
            arr[i] ^= arr[idx];
            arr[idx] ^= arr[i];
            arr[i] ^= arr[idx];
        }
        Arrays.sort(arr);
    }

    static void sort(long[] arr) {
        Random rand = new Random();
        int n = arr.length;
        for (int i = 0; i < n; i++) {
            int idx = rand.nextInt(n);
            if (idx == i) continue;
            arr[i] ^= arr[idx];
            arr[idx] ^= arr[i];
            arr[i] ^= arr[idx];
        }
        Arrays.sort(arr);
    }

    static void sortDec(int[] arr) {
        Random rand = new Random();
        int n = arr.length;
        for (int i = 0; i < n; i++) {
            int idx = rand.nextInt(n);
            if (idx == i) continue;
            arr[i] ^= arr[idx];
            arr[idx] ^= arr[i];
            arr[i] ^= arr[idx];
        }
        Arrays.sort(arr);
        int l = 0;
        int r = n - 1;
        while (l < r) {
            arr[l] ^= arr[r];
            arr[r] ^= arr[l];
            arr[l] ^= arr[r];
            l++;
            r--;
        }
    }

    static void sortDec(long[] arr) {
        Random rand = new Random();
        int n = arr.length;
        for (int i = 0; i < n; i++) {
            int idx = rand.nextInt(n);
            if (idx == i) continue;
            arr[i] ^= arr[idx];
            arr[idx] ^= arr[i];
            arr[i] ^= arr[idx];
        }
        Arrays.sort(arr);
        int l = 0;
        int r = n - 1;
        while (l < r) {
            arr[l] ^= arr[r];
            arr[r] ^= arr[l];
            arr[l] ^= arr[r];
            l++;
            r--;
        }
    }

    static class InputReader {
        private boolean finished = false;

        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private SpaceCharFilter filter;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (numChars == -1) {
                throw new InputMismatchException();
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }

        public int peek() {
            if (numChars == -1) {
                return -1;
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    return -1;
                }
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar];
        }

        public int nextInt() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public long nextLong() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public String nextString() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            StringBuilder res = new StringBuilder();
            do {
                if (Character.isValidCodePoint(c)) {
                    res.appendCodePoint(c);
                }
                c = read();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public boolean isSpaceChar(int c) {
            if (filter != null) {
                return filter.isSpaceChar(c);
            }
            return isWhitespace(c);
        }

        public static boolean isWhitespace(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        private String readLine0() {
            StringBuilder buf = new StringBuilder();
            int c = read();
            while (c != '\n' && c != -1) {
                if (c != '\r') {
                    buf.appendCodePoint(c);
                }
                c = read();
            }
            return buf.toString();
        }

        public String readLine() {
            String s = readLine0();
            while (s.trim().length() == 0) {
                s = readLine0();
            }
            return s;
        }

        public String readLine(boolean ignoreEmptyLines) {
            if (ignoreEmptyLines) {
                return readLine();
            } else {
                return readLine0();
            }
        }

        public BigInteger readBigInteger() {
            try {
                return new BigInteger(nextString());
            } catch (NumberFormatException e) {
                throw new InputMismatchException();
            }
        }

        public char nextCharacter() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            return (char) c;
        }

        public double nextDouble() {
            int c = read();
            while (isSpaceChar(c)) {
                c = read();
            }
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            double res = 0;
            while (!isSpaceChar(c) && c != '.') {
                if (c == 'e' || c == 'E') {
                    return res * Math.pow(10, nextInt());
                }
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = read();
            }
            if (c == '.') {
                c = read();
                double m = 1;
                while (!isSpaceChar(c)) {
                    if (c == 'e' || c == 'E') {
                        return res * Math.pow(10, nextInt());
                    }
                    if (c < '0' || c > '9') {
                        throw new InputMismatchException();
                    }
                    m /= 10;
                    res += (c - '0') * m;
                    c = read();
                }
            }
            return res * sgn;
        }

        public boolean isExhausted() {
            int value;
            while (isSpaceChar(value = peek()) && value != -1) {
                read();
            }
            return value == -1;
        }

        public String next() {
            return nextString();
        }

        public SpaceCharFilter getFilter() {
            return filter;
        }

        public void setFilter(SpaceCharFilter filter) {
            this.filter = filter;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);
        }

        public int[] nextIntArray(int n) {
            int[] array = new int[n];
            for (int i = 0; i < n; ++i) array[i] = nextInt();
            return array;
        }

        public int[] nextSortedIntArray(int n) {
            int array[] = nextIntArray(n);
            Arrays.sort(array);
            return array;
        }

        public int[] nextSumIntArray(int n) {
            int[] array = new int[n];
            array[0] = nextInt();
            for (int i = 1; i < n; ++i) array[i] = array[i - 1] + nextInt();
            return array;
        }

        public long[] nextLongArray(int n) {
            long[] array = new long[n];
            for (int i = 0; i < n; ++i) array[i] = nextLong();
            return array;
        }

        public long[] nextSumLongArray(int n) {
            long[] array = new long[n];
            array[0] = nextInt();
            for (int i = 1; i < n; ++i) array[i] = array[i - 1] + nextInt();
            return array;
        }

        public long[] nextSortedLongArray(int n) {
            long array[] = nextLongArray(n);
            Arrays.sort(array);
            return array;
        }
    }


}
