Submission #839350

#	Time	Username	Problem	Language	Result	Execution time	Memory
839350		tch1cherin	Strange Device (APIO19_strange_device)	C++17	100 / 100	630 ms	68988 KiB

strange_device

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

const long long INF = 2e18;

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int N;
  long long A, B;
  cin >> N >> A >> B;
  long long AI = A / gcd(A, B + 1);
  long long M = INF / AI >= B ? AI * B : INF;   
  vector<pair<long long, int>> events;
  for (int i = 0; i < N; i++) {
    long long L, R;
    cin >> L >> R;
    if (R - L >= M) {
      cout << M << "\n";
      exit(0);
    }
    if (R % M < L % M) {
      events.push_back({L % M, 1});
      events.push_back({M, -1});
      events.push_back({0, 1});
      events.push_back({R % M + 1, -1}); 
    } else {
      events.push_back({L % M, 1});
      events.push_back({R % M + 1, -1});
    }
  }
  sort(events.begin(), events.end());
  long long ans = 0, last = 0;
  int open = 0;
  for (auto [x, type] : events) {
    if (open != 0) {
      ans += x - last;
    }
    open += type;
    last = x;
  }
  cout << ans << "\n";
}

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