Submission #1258754

#	Time	Username	Problem	Language	Result	Execution time	Memory
1258754		trgbao	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	119 ms	150596 KiB

joi2019_ho_t1

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

string a[3005];
int fi[3005][3005];
int fo[3005][3005];

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int n, m;
    cin >> n >> m;
    for (int i = 1;i <= n;i++) {
        cin >> a[i];
        string s = " ";
        a[i] = s + a[i];
    }
    for (int i = 1;i<=n;i++){
        for (int j = 1; j <= m;j++) {
            fo[i][j] = fo[i][j-1] + (a[i][j] == 'O');
            fi[i][j] = fi[i-1][j] + (a[i][j] == 'I');
            // cout << i << " " << j << '\n';
            // cout << fo[i][j] << " " << fi[i][j] << '\n';
        }
    }
    int res = 0;
    for (int i = 1;i<=n;i++) {
        for (int j = 1;j<=m;j++) {
            if (a[i][j] == 'J') res += (fi[n][j] - fi[i][j]) * (fo[i][m] - fo[i][j]); 
            // cout << fi[n][j] - fi[i][j] << " " << fo[i][m] - fo[i][j] << '\n';
        }
    }
    cout << res;
    return 0;
}

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