Submission #230162

#	Time	Username	Problem	Language	Result	Execution time	Memory
230162		Haunted_Cpp	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	314 ms	80248 KiB

joi2019_ho_t1

#include <iostream>

using namespace std;

const int N = 3e3 + 5;

int dp_orb [N][N];
int dp_ingot [N][N];

char g [N][N];

int main () {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int r, c;
  cin >> r >> c;
  for (int i = 0; i < r; i++) {
    for (int j = 0; j < c; j++) {
      cin >> g[i][j];
    }
  }
  for (int i = 0; i < r; i++) {
    for (int j = c - 1; j >= 0; j--) {
      dp_orb[i][j] = (g[i][j] == 'O');
      if (j < c - 1) dp_orb[i][j] += dp_orb[i][j + 1];
    }
  }
  for (int i = 0; i < c; i++) {
    for (int j = r - 1; j >= 0; j--) {
      dp_ingot[i][j] = (g[j][i] == 'I');
      if (j < r - 1) dp_ingot[i][j] += dp_ingot[i][j + 1];
    }
  }
  long long res = 0;
  for (int i = 0; i < r; i++) {
    for (int j = 0; j < c; j++) {
      if (g[i][j] != 'J') continue;
      int tot_orb = (j + 1 < c ? dp_orb[i][j + 1] : 0);
      int tot_ingot = (i + 1 < r ? dp_ingot[j][i + 1] : 0);
      res += tot_orb * tot_ingot;
    }
  }
  cout << res << '\n';
  return 0;
}

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