Submission #1207436

#	Time	Username	Problem	Language	Result	Execution time	Memory
1207436		rhm_gan	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	187 ms	151280 KiB

joi2019_ho_t1

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

#ifdef LOCAL
#include "debug.h"
#else
#define dbg(...) 42
#endif

#define int long long

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m;
    cin >> n >> m;

    vector<string> a(n);
    vector<vector<int>> r(n, vector<int>(m));
    vector<vector<int>> c(n, vector<int>(m));

    for (int i = 0; i < n; i++) {
    	cin >> a[i];
    	for (int j = 0; j < m; j++) {
    		if (a[i][j] == 'O') {
    			r[i][j]++;
    		}
    		if (a[i][j] == 'I') {
    			c[i][j]++;
    		}
    	}
    }

    for (int i = 0; i < n; i++) {
    	for (int j = 0; j < m; j++) {
    		if (j > 0) r[i][j] += r[i][j - 1];
    		if (i > 0) c[i][j] += c[i - 1][j];
    	}
    }

    int res = 0;
    for (int i = 0; i < n; i++) {
    	for (int j = 0; j < m; j++) {
    		if (a[i][j] == 'J') {
    			res += (r[i][m - 1] - r[i][j]) * (c[n - 1][j] - c[i][j]);
    		}
    	}
    }

    cout << res << '\n';

    return 0;
}

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