#include <bits/stdc++.h>
using namespace std;
long long n, q, v[6000005][2], su[6000005], raod, ans, x, tt;
string second;
void add(long long x, long long sz) {
  su[x]++;
  if (sz == 33) return;
  long long t = second[sz] - '0';
  if (v[x][t] == 0) v[x][t] = raod, raod++;
  add(v[x][t], sz + 1);
}
void remove(long long x, long long sz) {
  su[x]--;
  if (sz == 33) return;
  long long t = second[sz] - '0';
  remove(v[x][t], sz + 1);
}
void qu(long long x, long long sz) {
  if (sz == 33) return;
  long long t = second[sz] - '0';
  if (t == 0 && su[v[x][1]]) {
    ans += 1 << (32 - sz);
    qu(v[x][1], sz + 1);
  } else if (t == 0) {
    qu(v[x][0], sz + 1);
  } else if (t == 1 && su[v[x][0]]) {
    ans += 1 << (32 - sz);
    qu(v[x][0], sz + 1);
  } else {
    qu(v[x][1], sz + 1);
  }
}
int main() {
  ios::sync_with_stdio(false);
  cin >> q;
  raod = 2;
  while (q--) {
    char c;
    cin >> c;
    cin >> x;
    long long xx = x;
    second = "";
    while (x) {
      second += (x % 2) + '0';
      x /= 2;
    }
    while ((int)second.size() != 33) second += '0';
    reverse(second.begin(), second.end());
    if (c == '+') add(1, 0), tt++;
    if (c == '-') remove(1, 0), tt--;
    if (c == '?') {
      ans = 0;
      qu(1, 0);
      cout << max(ans, xx) << endl;
    }
  }
  return 0;
}

### Prompt

Your challenge is to write a Cpp solution 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 n, q, v[6000005][2], su[6000005], raod, ans, x, tt;
string second;
void add(long long x, long long sz) {
  su[x]++;
  if (sz == 33) return;
  long long t = second[sz] - '0';
  if (v[x][t] == 0) v[x][t] = raod, raod++;
  add(v[x][t], sz + 1);
}
void remove(long long x, long long sz) {
  su[x]--;
  if (sz == 33) return;
  long long t = second[sz] - '0';
  remove(v[x][t], sz + 1);
}
void qu(long long x, long long sz) {
  if (sz == 33) return;
  long long t = second[sz] - '0';
  if (t == 0 && su[v[x][1]]) {
    ans += 1 << (32 - sz);
    qu(v[x][1], sz + 1);
  } else if (t == 0) {
    qu(v[x][0], sz + 1);
  } else if (t == 1 && su[v[x][0]]) {
    ans += 1 << (32 - sz);
    qu(v[x][0], sz + 1);
  } else {
    qu(v[x][1], sz + 1);
  }
}
int main() {
  ios::sync_with_stdio(false);
  cin >> q;
  raod = 2;
  while (q--) {
    char c;
    cin >> c;
    cin >> x;
    long long xx = x;
    second = "";
    while (x) {
      second += (x % 2) + '0';
      x /= 2;
    }
    while ((int)second.size() != 33) second += '0';
    reverse(second.begin(), second.end());
    if (c == '+') add(1, 0), tt++;
    if (c == '-') remove(1, 0), tt--;
    if (c == '?') {
      ans = 0;
      qu(1, 0);
      cout << max(ans, xx) << endl;
    }
  }
  return 0;
}

```