Submission #500676

#	Time	Username	Problem	Language	Result	Execution time	Memory
500676		600Mihnea	Sails (IOI07_sails)	C++17	70 / 100	1099 ms	2308 KiB

sails

#include <bits/stdc++.h>

using namespace std;

#define int long long

int gauss(int x) {
  return x * (x + 1) / 2;
}

struct Data {
  int total;
  int need;
};

bool operator < (Data a, Data b) {
  return a.total < b.total;
}

const int N = (int) 1e5 + 7;
const int INF = (int) 1e18;
int n;
int cnt[N];
Data guys[N];

signed main() {
  ios::sync_with_stdio(0); cin.tie(0);
  //freopen ("input", "r", stdin);
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> guys[i].total >> guys[i].need;
  }
  sort(guys + 1, guys + n + 1);

  for (int i = 1; i <= n; i++) {
    int total = guys[i].total;
    int need = guys[i].need;
    /// cnt e in ordine ordine descrescatoare
    int L = total - need + 1;
    int R = total;
    int cntL = cnt[L];
    int Lfirst = L, Llast = L;
    /// binary search to find them
    {
      int low = 1, high = L;
      while (low <= high) {
        int mid = (low + high) / 2;
        if (cnt[mid] == cnt[L]) {
          Lfirst = mid;
          high = mid - 1;
        } else {
          low = mid + 1;
        }
      }
    }
    {
      int low = L, high = total;
      while (low <= high) {
        int mid = (low + high) / 2;
        if (cnt[mid] == cnt[L]) {
          Llast = mid;
          low = mid + 1;
        } else {
          high = mid - 1;
        }
      }
    }
    int cntOfL = Llast - L + 1;
    int firstActual = Lfirst;
    int lastActual = Lfirst + cntOfL - 1;
    for (int j = firstActual; j <= lastActual; j++) {
      cnt[j]++;
    }
    for (int j = Llast + 1; j <= R; j++) {
      cnt[j]++;
    }
    for (int j = 2; j <= total; j++) {
      assert(cnt[j - 1] >= cnt[j]);
    }
  }

  int total = 0;

  for (int i = 1; i < N; i++) {
    total += gauss(cnt[i] - 1);
  }

  cout << total << "\n";

  return 0;
}

Compilation message (stderr)

sails.cpp: In function 'int main()':
sails.cpp:41:9: warning: unused variable 'cntL' [-Wunused-variable]
   41 |     int cntL = cnt[L];
      |         ^~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 5 / 5
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10
• Subtask 11: 0 / 10