Submission #360139

#	Time	Username	Problem	Language	Result	Execution time	Memory
360139		Pety	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	300 ms	123912 KiB

joi2019_ho_t1

#include <bits/stdc++.h>

using namespace std;

int n, m, dp[3002][3002][3], nr[3002][3];
char ch[] = "JOI";
char v[3002][3002];


int main()
{
  ios_base::sync_with_stdio(false);
  cin.tie(0); cout.tie(0);
  cin >> n >> m;
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= m; j++)
      cin >> v[i][j];
  for (int i = n; i >= 1; i--)
    for (int j = 1; j <= m; j++)
      for (int k = 0; k < 3; k++)
        dp[i][j][k] = dp[i + 1][j][k] + (v[i][j] == ch[k]);
  long long ans = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = m; j >= 1; j--) {
      for (int k = 0; k < 3; k++)
        nr[j][k] = nr[j + 1][k] + (v[i][j] == ch[k]);
      if (v[i][j] == 'J')
        ans += 1ll * dp[i + 1][j][2] * nr[j + 1][1];
      //if (v[i][j] == 'O')
        //ans += 1ll * dp[i + 1][j][0] * nr[j + 1][2] + 1ll * dp[i + 1][j][2] * nr[j + 1][0];
      //if (v[i][j] == 'I')
        //ans += 1ll * dp[i + 1][j][1] * nr[j + 1][0] + 1ll * dp[i + 1][j][0] * nr[j + 1][1];
    }
  }
  cout << ans;
  return 0;
}

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