#include <bits/stdc++.h>
using namespace std;
long long q, x, idx;
string s;
struct data {
  long long arr[3];
  long long cnt[3];
} trie[100005 * 33];
void insrt(long long z) {
  long long now = 0;
  for (long long i = 31; i >= 0; i--) {
    bool x = (z & (1 << i));
    if (trie[now].arr[x] == 0) {
      trie[now].arr[x] = ++idx;
    }
    trie[now].cnt[x]++;
    now = trie[now].arr[x];
  }
}
void del(long long z) {
  long long now = 0;
  for (long long i = 31; i >= 0; i--) {
    bool x = (z & (1 << i));
    trie[now].cnt[x]--;
    now = trie[now].arr[x];
  }
}
long long qry(long long z) {
  long long now = 0, ans = 0;
  for (long long i = 31; i >= 0; i--) {
    bool x = (z & (1 << i));
    if (trie[now].arr[x ^ 1] != 0 && trie[now].cnt[x ^ 1] >= 1) {
      ans |= (1 << i);
      now = trie[now].arr[x ^ 1];
    } else
      now = trie[now].arr[x];
  }
  return ans;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  insrt(0);
  cin >> q;
  while (q--) {
    cin >> s >> x;
    if (s == "+")
      insrt(x);
    else if (s == "-")
      del(x);
    else
      cout << qry(x) << endl;
  }
  return 0;
}

### Prompt

Your task is to create 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 q, x, idx;
string s;
struct data {
  long long arr[3];
  long long cnt[3];
} trie[100005 * 33];
void insrt(long long z) {
  long long now = 0;
  for (long long i = 31; i >= 0; i--) {
    bool x = (z & (1 << i));
    if (trie[now].arr[x] == 0) {
      trie[now].arr[x] = ++idx;
    }
    trie[now].cnt[x]++;
    now = trie[now].arr[x];
  }
}
void del(long long z) {
  long long now = 0;
  for (long long i = 31; i >= 0; i--) {
    bool x = (z & (1 << i));
    trie[now].cnt[x]--;
    now = trie[now].arr[x];
  }
}
long long qry(long long z) {
  long long now = 0, ans = 0;
  for (long long i = 31; i >= 0; i--) {
    bool x = (z & (1 << i));
    if (trie[now].arr[x ^ 1] != 0 && trie[now].cnt[x ^ 1] >= 1) {
      ans |= (1 << i);
      now = trie[now].arr[x ^ 1];
    } else
      now = trie[now].arr[x];
  }
  return ans;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  insrt(0);
  cin >> q;
  while (q--) {
    cin >> s >> x;
    if (s == "+")
      insrt(x);
    else if (s == "-")
      del(x);
    else
      cout << qry(x) << endl;
  }
  return 0;
}

```