Submission #1173845

#	Time	Username	Problem	Language	Result	Execution time	Memory
1173845		khangrl	Collecting Mushrooms (NOI18_collectmushrooms)	C++20	100 / 100	398 ms	67440 KiB

mushrooms

#include<bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define ll long long
using namespace std;
int main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	vector <pair <int, int> > mush, sprink; 
	int n, m, d, k, ans=0;
	cin>>n>>m>>d>>k;
	char c[n+5][m+5];
	for(int i=1; i<=n; i++){
		for(int j=1; j<=m; j++){
			cin>>c[i][j];
			if(c[i][j]=='S'){
				sprink.pb({i, j});
			}
		}
	}
	map <int, map <int, int> > mp;
	for(auto spn : sprink){
		int x=spn.ff, y=spn.ss;
		int first_x=max(1, x-d), last_x=min(n, x+d), first_y=max(1, y-d), last_y=min(m, y+d);
		mp[first_x][first_y]++;
		mp[last_x+1][last_y+1]++;
		mp[first_x][last_y+1]--;
		mp[last_x+1][first_y]--;
	}
	for(int i=1; i<=n; i++){
		for(int j=1; j<=m; j++){
			mp[i][j]+=mp[i][j-1];
		}
	}

	for(int i=1; i<=m; i++){
		for(int j=1; j<=n; j++){
			mp[j][i]+=mp[j-1][i];
		}
	}
	for(int i=1; i<=n; i++){
		for(int j=1; j<=m; j++){
			if(c[i][j]=='M' and mp[i][j]>=k){
				ans++;
			}
		}
	}
	cout<<ans;
}
/*
5 5 2 2
....M
.M...
..S..
.S...
...M.
*/

• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 18 / 18
• Subtask 4: 23 / 23
• Subtask 5: 19 / 19
• Subtask 6: 21 / 21