#include <bits/stdc++.h>
using namespace std;
long long int q, x;
char t;
set<long long int> inset;
map<int, int> cnt;
long long int fin(long long int tar) {
  long long int temp = tar;
  int bin[31] = {0};
  int create[33];
  int uppbound[33];
  int d = 0;
  while (tar != 0) {
    bin[d] = tar % 2;
    tar /= 2;
    d++;
  }
  d--;
  long long int lcut = 0, rcut = 0;
  for (int i = 30; i >= 0; i--) {
    lcut += (1 - bin[i]) * (1 << i);
    rcut = lcut + (1 << i);
    if (inset.lower_bound(lcut) == inset.lower_bound(rcut)) {
      lcut += (2 * bin[i] - 1) * (1 << i);
    }
  }
  return max(lcut ^ temp, temp);
}
int main(void) {
  int i, j;
  scanf("%lld", &q);
  for (i = 1; i <= q; i++) {
    cin >> t >> x;
    if (t == '+') {
      cnt[x]++;
      if (cnt[x] == 1) {
        inset.insert(x);
      }
    } else if (t == '-') {
      cnt[x]--;
      if (cnt[x] == 0) {
        inset.erase(x);
      }
    } else if (t == '?') {
      printf("%lld\n", fin(x));
    }
  }
  return 0;
}

### 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;
long long int q, x;
char t;
set<long long int> inset;
map<int, int> cnt;
long long int fin(long long int tar) {
  long long int temp = tar;
  int bin[31] = {0};
  int create[33];
  int uppbound[33];
  int d = 0;
  while (tar != 0) {
    bin[d] = tar % 2;
    tar /= 2;
    d++;
  }
  d--;
  long long int lcut = 0, rcut = 0;
  for (int i = 30; i >= 0; i--) {
    lcut += (1 - bin[i]) * (1 << i);
    rcut = lcut + (1 << i);
    if (inset.lower_bound(lcut) == inset.lower_bound(rcut)) {
      lcut += (2 * bin[i] - 1) * (1 << i);
    }
  }
  return max(lcut ^ temp, temp);
}
int main(void) {
  int i, j;
  scanf("%lld", &q);
  for (i = 1; i <= q; i++) {
    cin >> t >> x;
    if (t == '+') {
      cnt[x]++;
      if (cnt[x] == 1) {
        inset.insert(x);
      }
    } else if (t == '-') {
      cnt[x]--;
      if (cnt[x] == 0) {
        inset.erase(x);
      }
    } else if (t == '?') {
      printf("%lld\n", fin(x));
    }
  }
  return 0;
}

```