Submission #949346

#	Time	Username	Problem	Language	Result	Execution time	Memory
949346		tnknguyen_	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	179 ms	160080 KiB

joi2019_ho_t1

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

const int sz = 3005;
char a[sz][sz];
int s[3][sz][sz];

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    //freopen("JOI19_ho_t1.inp","r",stdin);
    //freopen("JOI19_ho_t1.out","w",stdout);

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

    for(int i=1; i<=n; ++i){
        for(int j=1; j<=m; ++j){
            cin>>a[i][j];
            s[0][i][j] = s[0][i][j-1] + (a[i][j] == 'O');
            s[1][i][j] = s[1][i-1][j] + (a[i][j] == 'I');
        }
    }

    int ans = 0;
    for(int i=1; i<=n; ++i){
        for(int j=1; j<=m; ++j){
            if(a[i][j] == 'J'){
                int x = s[1][n][j] - s[1][i][j];
                int y = s[0][i][m] - s[0][i][j];
                ans += (x * y);
            }
        }
    }
    cout<<ans;

    return 0;
}

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