Submission #1005982

#	Time	Username	Problem	Language	Result	Execution time	Memory
1005982		makanhulia	Collecting Mushrooms (NOI18_collectmushrooms)	C++17	100 / 100	26 ms	36048 KiB

mushrooms

#include <bits/stdc++.h>
using namespace std;
#define int long long
int r, c, d, s, jum;
vector<pair<int, int>> v;
signed main() {
  ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
  cin >> r >> c >> d >> s;
  char arr[r + 5][c + 5];
  int pref[r + 5][c + 5];
  for(int i = 1; i <= r; i++) {
    for(int j = 1; j <= c; j++) {
      cin >> arr[i][j];
      if(arr[i][j] == 'M') {
        v.push_back({i, j});
      }
    }
  }
  for(int i = 1; i <= r; i++) {
    for(int j = 1; j <= c; j++) {
      if(arr[i][j] == 'S') {
        pref[i][j] = pref[i][j - 1] + pref[i - 1][j] - pref[i - 1][j - 1] + 1;
      } else {
        pref[i][j] = pref[i][j - 1] + pref[i - 1][j] - pref[i - 1][j - 1];
      }
    }
  }
  for(int i = 0; i < v.size(); i++) {
    int a = v[i].first, b = v[i].second;
    int lr, lc, hr, hc;
    lr = max(0ll, a - d - 1);
    lc = max(0ll, b - d - 1);
    hr = min(r, a + d);
    hc = min(c, b + d);
    int funi = pref[hr][hc] - pref[lr][hc] - pref[hr][lc] + pref[lr][lc];
    if(funi >= s) {
      jum++;
    }
  }
  cout << jum << "\n";
  
}

Compilation message (stderr)

mushrooms.cpp: In function 'int main()':
mushrooms.cpp:28:20: 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]
   28 |   for(int i = 0; i < v.size(); i++) {
      |                  ~~^~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 18 / 18
• Subtask 4: 23 / 23
• Subtask 5: 19 / 19
• Subtask 6: 21 / 21