Submission #1166380

#	Time	Username	Problem	Language	Result	Execution time	Memory
1166380		altern23	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	305 ms	150964 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define pii pair<ll, ll>
#define fi first
#define sec second
#define ld long double

const ll N = 2e5;
const ll INF = 4e18;
const ll MOD = 1e9 + 7;

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int tc = 1;
    // cin >> tc;
    for(;tc--;){
        ll n, m; cin >> n >> m;
        vector<vector<ll>> sf1(n + 5, vector<ll>(m + 5)), sf2(n + 5, vector<ll>(m + 5));
        vector<vector<char>> grid(n + 5, vector<char>(m + 5));
        for(int i = 1; i <= n; i++){
            for(int j = 1; j <= m; j++){
                cin >> grid[i][j];
            }
        }

        for(int i = 1; i <= n; i++){
            for(int j = m; j >= 1; --j){
                sf1[i][j] = sf1[i][j + 1] + (grid[i][j] == 'O');
            }
        }

        for(int j = 1; j <= m; j++){
            for(int i = n; i >= 1; --i){
                sf2[i][j] = sf2[i + 1][j] + (grid[i][j] == 'I');
            }
        }

        ll ans = 0;
        for(int i = 1; i <= n; i++){
            for(int j = 1; j <= m; j++){
                if(grid[i][j] == 'J') ans += sf1[i][j] * sf2[i][j];
            }
        }
        
        cout << ans << "\n";
    }   
}

/*

*/ 

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