Submission #1306348

#	Time	Username	Problem	Language	Result	Execution time	Memory
1306348		khanhphucscratch	Bitaro the Brave (JOI19_ho_t1)	C++20	100 / 100	311 ms	150412 KiB

joi2019_ho_t1

#include<bits/stdc++.h>
#define int long long
using namespace std;
int cd[2][3005][3005];
char a[3005][3005];
signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n, m; cin>>n>>m;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            cin>>a[i][j];
            if(a[i][j] == 'O') cd[0][i][j] = 1;
            if(a[i][j] == 'I') cd[1][i][j] = 1;
        }
    }
    for(int i = 1; i <= n; i++){
        for(int j = m; j >= 1; j--) cd[0][i][j] += cd[0][i][j+1];
    }
    for(int j = 1; j <= m; j++){
        for(int i = n; i >= 1; i--) cd[1][i][j] += cd[1][i+1][j];
    }
    int ans = 0;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++) if(a[i][j] == 'J') ans += cd[0][i][j] * cd[1][i][j];
    }
    cout<<ans;
}

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