Submission #610978

#	Time	Username	Problem	Language	Result	Execution time	Memory
610978		four_specks	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	207 ms	160096 KiB

joi2019_ho_t1

#include <bits/stdc++.h>

using namespace std;

inline namespace
{
} // namespace

void solve()
{
    int n, m;
    cin >> n >> m;

    vector<string> a(n);
    for (string &s : a)
        cin >> s;

    vector suff1(n, vector<long>(m + 1, 0)), suff2(m, vector<long>(n + 1, 0));
    for (int i = 0; i < n; i++)
    {
        for (int j = m - 1; j >= 0; j--)
            suff1[i][j] = suff1[i][j + 1] + (a[i][j] == 'O');
    }
    for (int i = 0; i < m; i++)
    {
        for (int j = n - 1; j >= 0; j--)
            suff2[i][j] = suff2[i][j + 1] + (a[j][i] == 'I');
    }

    long res = 0;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < m; j++)
        {
            if (a[i][j] == 'J')
                res += suff1[i][j] * suff2[j][i];
        }
    }

    cout << res << '\n';
}

int main()
{
    ios_base::sync_with_stdio(false), cin.tie(NULL);

    solve();

    return 0;
}

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