Submission #1280602

#	Time	Username	Problem	Language	Result	Execution time	Memory
1280602		aliali	Collecting Mushrooms (NOI18_collectmushrooms)	C++20	100 / 100	14 ms	12784 KiB

mushrooms

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

//@author: abdinabiev

const int N = 1e6 + 12, INF = 1e18;

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
	int r, c, d, k;
	cin >>r >>c >>d >>k;
    vector<string> a(r + 1);
    for (int i = 1; i <= r; ++i) {
        string s; cin >>s;
        a[i] = s; 
    }
    vector<vector<int>> ps(r + 1, vector<int>(c + 1, 0));
    for (int i = 1; i <= r; ++i) {
        for (int j = 1; j <= c; ++j) {
            if (a[i][j - 1] == 'S') ps[i][j] = 1;
        }
    }
    for (int i = 1; i <= r; ++i) {
        for (int j = 1; j <= c; ++j) {
            ps[i][j] += ps[i - 1][j] + ps[i][j - 1] - ps[i - 1][j - 1];
        }
    }
    int ans = 0;
    for (int i = 1; i <= r; ++i) {
        for (int j = 1; j <= c; ++j) {
            if (a[i][j - 1] != 'M') continue;
            int r1 = max((int)1, i - d);
            int c1 = max((int)1, j - d);
            int r2 = min(r, i + d);
            int c2 = min(c, j + d);
            int cnt = ps[r2][c2] - ps[r1 - 1][c2] - ps[r2][c1 - 1] + ps[r1 - 1][c1 - 1];
            if (cnt >= k) ans++;
        }
    }
    cout <<ans <<'\n';
}

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