Submission #339468

#	Time	Username	Problem	Language	Result	Execution time	Memory
339468		bigDuck	Bitaro the Brave (JOI19_ho_t1)	C++14	100 / 100	307 ms	79852 KiB

joi2019_ho_t1

#include<bits/stdc++.h>
using namespace std;
#define INIT  ios_base :: sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define mp make_pair
#define pb push_back
#define ft first
#define sc second
#define ll long long
#define pii pair<int, int>
#define count_bits __builtin_popcount


char a[3010][3010];
int n, m;
int ing[3010][3010], orb[3010][3010];



int32_t main(){
INIT
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]=='I'){
            ing[i][j]++;
        }
        if(a[i][j]=='O'){
            orb[i][j]++;
        }
    }
}

ll res=0;
for(int i=n; i>=1; i--){
    for(int j=m; j>=1; j--){
        orb[i][j]=orb[i][j+1]+orb[i][j];
        ing[i][j]=ing[i+1][j]+ing[i][j];
        if(a[i][j]=='J'){
            res+=((ll)ing[i][j])*((ll)orb[i][j]);
        }
    }
}
cout<<res;



return 0;
}

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