Submission #784496

#	Time	Username	Problem	Language	Result	Execution time	Memory
784496		andecaandeci	Strange Device (APIO19_strange_device)	C++17	5 / 100	1354 ms	33400 KiB

strange_device

#include <bits/stdc++.h>
using namespace std;

#define int long long
// #define i128 long long
#define i128 __int128_t

int n, a, b;
vector<pair<int, int>> sg;
const int maks = 1e18;

// i128 gcd(i128 a, i128 b) {
//   if (b == 0) return a;
//   return gcd(b, a%b);
// }

bool comp(pair<int, int> a, pair<int, int> b) {
  return a.first < b.first or (a.first == b.first and a.second < b.second);
}

signed main() {
  i128 temp;
  // int temp;
  int size;
  cin >> n >> a >> b;
  temp = (a/__gcd(a,b+1))*b;
  // if ((b+1 % a) == 0) size = b;
  // if (temp > maks) size = maks;
  // else size = temp;
  size = temp;

  int l, r;
  for (int i = 0; i < n; i++) {
    cin >> l >> r;
    // cout << l << " " << r << endl;
    if (r - l + 1 >= size) {
      cout << size << endl;
      return 0;
    } else if (l%size > r%size) {
      sg.push_back({l%size, 1});
      sg.push_back({size-1, 2});
      sg.push_back({0, 1});
      sg.push_back({r%size, 2});
    } else {
      sg.push_back({l%size, 1});
      sg.push_back({r%size, 2});
    }
  }
  sort(sg.begin(), sg.end());

  int cnt = 0, l2, ans = 0;
  // vector<pair<int, int>> ans;
  for (int i = 0; i < sg.size(); i++) {
    // cout << sg[i].first << " " << sg[i].second << endl;
    if (sg[i].second == 1) {
      if (cnt == 0) l2 = sg[i].first;
      cnt++;
    } else cnt--;

    if (cnt == 0) {
      // ans.push_back({l2, sg[i].first});
      ans += sg[i].first-l2+1.;
    }
  }
  cout << ans << endl;

  // int res = 0;
  // for (auto i: ans) {
  //   // cout << i.first << " " << i.second << endl;
  //   res += (i.second - i.first + 1);
  // }
  // cout << res << endl;

}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:53:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   53 |   for (int i = 0; i < sg.size(); i++) {
      |                   ~~^~~~~~~~~~~
strange_device.cpp:62:25: warning: 'l2' may be used uninitialized in this function [-Wmaybe-uninitialized]
   62 |       ans += sg[i].first-l2+1.;

• Subtask 1: 0 / 10
• Subtask 2: 0 / 5
• Subtask 3: 5 / 5
• Subtask 4: 0 / 5
• Subtask 5: 0 / 5
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20
• Subtask 8: 0 / 30