#include <bits/stdc++.h>
using namespace std;
inline char get_char();
const int N = 3e6 + 10;
int T, n, cnt = 1;
int c[40], trie[N][3];
int rec[N];
inline void change(long long x) {
  memset(c, 0, sizeof(c));
  int ct = 0;
  while (x) c[++ct] = x & 1, x >>= 1;
}
inline int reply() {
  int p = 1, s = 0;
  for (register int i = 33; i >= 1; i--) {
    int &k = c[i];
    s <<= 1;
    if (!trie[p][k ^ 1] or !rec[trie[p][k ^ 1]]) {
      if (trie[p][k] and rec[trie[p][k]])
        p = trie[p][k];
      else
        break;
    } else
      p = trie[p][k ^ 1], s |= 1;
  }
  return s;
}
inline void insert() {
  int p = 1;
  for (register int i = 33; i >= 1; i--) {
    int &k = c[i];
    if (!trie[p][k]) trie[p][k] = ++cnt;
    p = trie[p][k], rec[p]++;
  }
}
inline void _delete() {
  int p = 1;
  for (register int i = 33; i >= 1; i--) {
    int &k = c[i];
    if (!trie[p][k] or !rec[trie[p][k]]) return;
    p = trie[p][k];
    rec[p]--;
  }
}
int main() {
  scanf("%d", &n);
  insert();
  while (n--) {
    static char c;
    static int x;
    c = get_char();
    scanf("%d", &x);
    change(x);
    if (c == '?')
      printf("%d\n", reply());
    else if (c == '+')
      insert();
    else
      _delete();
  }
  return 0;
}
inline char get_char() {
  register char c = getchar();
  while (c != '+' and c != '-' and c != '?') c = getchar();
  return c;
}

### Prompt

Please create a solution in CPP to the following problem:

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>.

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
inline char get_char();
const int N = 3e6 + 10;
int T, n, cnt = 1;
int c[40], trie[N][3];
int rec[N];
inline void change(long long x) {
  memset(c, 0, sizeof(c));
  int ct = 0;
  while (x) c[++ct] = x & 1, x >>= 1;
}
inline int reply() {
  int p = 1, s = 0;
  for (register int i = 33; i >= 1; i--) {
    int &k = c[i];
    s <<= 1;
    if (!trie[p][k ^ 1] or !rec[trie[p][k ^ 1]]) {
      if (trie[p][k] and rec[trie[p][k]])
        p = trie[p][k];
      else
        break;
    } else
      p = trie[p][k ^ 1], s |= 1;
  }
  return s;
}
inline void insert() {
  int p = 1;
  for (register int i = 33; i >= 1; i--) {
    int &k = c[i];
    if (!trie[p][k]) trie[p][k] = ++cnt;
    p = trie[p][k], rec[p]++;
  }
}
inline void _delete() {
  int p = 1;
  for (register int i = 33; i >= 1; i--) {
    int &k = c[i];
    if (!trie[p][k] or !rec[trie[p][k]]) return;
    p = trie[p][k];
    rec[p]--;
  }
}
int main() {
  scanf("%d", &n);
  insert();
  while (n--) {
    static char c;
    static int x;
    c = get_char();
    scanf("%d", &x);
    change(x);
    if (c == '?')
      printf("%d\n", reply());
    else if (c == '+')
      insert();
    else
      _delete();
  }
  return 0;
}
inline char get_char() {
  register char c = getchar();
  while (c != '+' and c != '-' and c != '?') c = getchar();
  return c;
}

```