Submission #1287184

#	Time	Username	Problem	Language	Result	Execution time	Memory
1287184		harryleee	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	189 ms	79920 KiB

joi2019_ho_t1

#include<bits/stdc++.h>
using namespace std;
const int maxn = 3e3;
int n, m, O[maxn + 1][maxn + 1], I[maxn + 1][maxn + 1];
string s[maxn + 1];
long long res = 0;

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> n >> m;
    for (int i = 1; i <= n; ++i){
        cin >> s[i];
        s[i] = " " + s[i];
    }

    for (int i = 1; i <= n; ++i){
        for (int j = 1; j <= m; ++j){
            O[i][j] = O[i][j - 1] + (s[i][j] == 'O');
        }
    }

    for (int j = 1; j <= m; ++j){
        for (int i = 1; i <= n; ++i){
            I[i][j] = I[i - 1][j] + (s[i][j] == 'I');
        }
    }

    for (int i = 1; i <= n; ++i){
        for (int j = 1; j <= m; ++j) if (s[i][j] == 'J'){
            res += (O[i][m] - O[i][j - 1]) * (I[n][j] - I[i - 1][j]);
        }
    }

    cout << res;
    return 0;
}

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