Submission #1291460

#	Time	Username	Problem	Language	Result	Execution time	Memory
1291460		hynmj	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	179 ms	150360 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
#define int long long
using namespace std;
const long long N = 2e5 + 5;
char a[3005][3005];
int so[3005][3005];
int si[3005][3005];
void solve()
{
    int n, m;
    cin >> n >> m;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            cin >> a[i][j];
        }
    }

    for (int i = 0; i < n; i++)
    {
        for (int j = m; j >= 0; j--)
        {
            so[i][j] += so[i][j + 1] + (a[i][j] == 'O');
        }
    }
    for (int i = n; i >= 0; i--)
    {
        for (int j = 0; j < m; j++)
        {
            si[i][j] += si[i + 1][j] + (a[i][j] == 'I');
        }
    }

    int ans = 0;

    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            if (a[i][j] == 'J')
            {
                ans += si[i][j] * so[i][j];
            }
        }
    }
    // for (int i = 0; i < n; i++)
    // {
    //     for (int j = 0; j < m; j++)
    //     {
    //         cout << a[i][j] << endl;
    //     }
    // }
    cout << ans << endl;
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);
    int t = 1;
    // cin >> t;
    for (int i = 1; i <= t; i++)
    {
        // cout << "Case #" << i << ':' << ' ';
        solve();
        cout << endl;
    }
    return 0;
}

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