Submission #926128

#	Time	Username	Problem	Language	Result	Execution time	Memory
926128		pragmatist	Collecting Mushrooms (NOI18_collectmushrooms)	C++17	100 / 100	17 ms	13664 KiB

mushrooms

#include<iostream>
#include<cassert>
#include<cmath>
#include<cstring>
#include<algorithm>
#include<vector>
#include<stack>
#include<set>
#include<queue>
#include<map>

using namespace std;

const int N = (int)4e5 + 7;
const int inf = (int)1e9 + 7;
const int MOD = (int)998244353;
const long long INF = (long long)1e18 + 7; 

int mult(int x, int y) {
	return 1ll*x*y%MOD;
}

int sum(int x, int y) {
	x += y;
	if(x >= MOD) {
		x -= MOD;
	}
	return x;
}

int sub(int x, int y) {
	x -= y;
	if(x < 0) {
		x += MOD;
	}
	return x;
}

int n, m, d, k;

int main() {	
	ios_base::sync_with_stdio(NULL);
	cin.tie(0);
	cin >> n >> m >> d >> k;
	char a[n+1][m+1];
	int b[n+5][m+5];
	memset(b, 0, sizeof(b));
	for(int i = 1; i <= n; ++i) {
		for(int j = 1; j <= m; ++j) {
			cin >> a[i][j];
		}
	}
	for(int i = 1; i <= n; ++i) {
		for(int j = 1; j <= m; ++j) {
			if(a[i][j] == 'S') {
				int x1 = max(1, i-d);
				int y1 = max(1, j-d);
				int x2 = min(n, i+d);
				int y2 = min(m, j+d);
				b[x1][y1]++;
				b[x1][y2+1]--;
				b[x2+1][y1]--;
				b[x2+1][y2+1]++;
			}
		}
	}
	for(int i = 1; i <= n; ++i) {
		for(int j = 1; j <= m; ++j) {
			b[i][j]+=b[i-1][j];
			b[i][j]+=b[i][j-1];
			b[i][j]-=b[i-1][j-1];
		}
	}
	int ans = 0;
	for(int i = 1; i <= n; ++i) {
		for(int j = 1; j <= m; ++j) {
			ans += (a[i][j] == 'M' && b[i][j] >= k);
		}
	}
	cout << ans;
	return 0;
}

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