Submission #764230

#	Time	Username	Problem	Language	Result	Execution time	Memory
764230		ind1v	Bitaro the Brave (JOI19_ho_t1)	C++11	100 / 100	303 ms	88504 KiB

joi2019_ho_t1

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

const int N = 3005;

int n, m;
char a[N][N];
int co[N][N], ci[N][N];

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      cin >> a[i][j];
    }
  }
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      co[i][j] = co[i][j - 1] + (a[i][j] == 'O');
    }
  }
  for (int j = 1; j <= m; j++) {
    for (int i = 1; i <= n; i++) {
      ci[i][j] = ci[i - 1][j] + (a[i][j] == 'I');
    }
  }
  long long ans = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      if (a[i][j] == 'J') {
        ans += 1LL * (co[i][m] - co[i][j]) * (ci[n][j] - ci[i][j]);
      }
    }
  }
  cout << ans;
  return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 50 / 50