Submission #862547

#	Time	Username	Problem	Language	Result	Execution time	Memory
862547		Ninedesu	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	289 ms	159264 KiB

joi2019_ho_t1

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

const int N=3002;
int n,m;
ll ans;
ll dpi[N][N],dpo[N][N];
string s,mp[N];

int main(){
    ios_base::sync_with_stdio(0),cin.tie(0);
    cin >> n >> m;
    for(int i=1; i<=n; i++){
        cin >> s;
        mp[i]="x"+s;
    }
    for(int i=n; i>=1; i--){
        for(int j=1; j<=m; j++){
            dpi[i][j]=dpi[i+1][j];
            if(mp[i][j]=='I')dpi[i][j]++;
        }
    }
    for(int j=m; j>=1; j--){
        for(int i=1; i<=n; i++){
            dpo[i][j]=dpo[i][j+1];
            if(mp[i][j]=='O')dpo[i][j]++;
        }
    }
    for(int i=1; i<=n; i++){
        for(int j=1; j<=m; j++){
            if(mp[i][j]=='J'&&dpi[i][j]&&dpo[i][j])ans+=dpi[i][j]*dpo[i][j];
        }
    }
    cout << ans;

    return 0;
}

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