Submission #949370

#	Time	Username	Problem	Language	Result	Execution time	Memory
949370		PM1	Bitaro the Brave (JOI19_ho_t1)	C++17	100 / 100	71 ms	79956 KiB

joi2019_ho_t1

#include <bits/stdc++.h>
using namespace std;
#define ll long long
const int mxn=3e3+5;
int n,m;
string s;
char c[mxn][mxn];
int rast[mxn][mxn],pain[mxn][mxn];
ll ans;
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>m;
	for(int i=0;i<n;i++){
		cin>>s;
		for(int j=0;j<m;j++)
			c[i][j]=s[j];
	}
	for(int i=n-1;i>=0;i--){
		for(int j=m-1;j>=0;j--){
			if(i!=n-1)pain[i][j]=pain[i+1][j]+(c[i+1][j]=='I');
			if(j!=m-1)rast[i][j]=rast[i][j+1]+(c[i][j+1]=='O');
			if(c[i][j]=='J')ans+=(ll)pain[i][j]*rast[i][j];
		}
	}
	cout<<ans;
	return 0;
}

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