Submission #1006071

#	Time	Username	Problem	Language	Result	Execution time	Memory
1006071		kebine	Collecting Mushrooms (NOI18_collectmushrooms)	C++17	100 / 100	17 ms	24560 KiB

mushrooms

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define endl "\n"


signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0);

    int n, m, d, s; cin >> n >> m >> d >> s;

    string grid[n + 5];

    for ( int i = 0; i < n; i++) cin >> grid[i];

    int ans[n + 5][m + 5];

    memset ( ans, 0, sizeof(ans));

    for ( int i = 0; i < n; i++){
        for ( int j = 0; j < m; j++){
            if ( grid[i][j] == 'S' ){
                int x1 = max ( 0ll, i - d), x2 = min ( n, i + d);
                int y1 = max ( 0ll, j - d ), y2 = min ( m, j + d);

                ans[x1][y1]++;
                
                if ( y2 + 1 < m ) ans[x1][y2 + 1]--;
                if ( x2 + 1 < n ) ans[x2 + 1][y1]--;
                if ( x2 + 1 < n && y2 + 1 < m ) ans[x2 + 1][y2 + 1]++;
            }
        }
    }

    int cnt = 0;

    for ( int i = 0; i < n; i++){
        for ( int j = 0; j < m; j++){
            if ( i - 1 >= 0 ){
                ans[i][j] += ans[i - 1][j];
            }
            if ( j - 1 >= 0 ){
                ans[i][j] += ans[i][j - 1];
            }
            if ( i - 1 >= 0 && j - 1 >= 0 ){
                ans[i][j] -= ans[i - 1][j - 1];
            }
        }
    }


    for ( int i = 0; i < n; i++){
        for ( int j = 0; j < m; j++){
            if ( grid[i][j] == 'M' ){
                if ( ans[i][j] >= s ) cnt++; 
            }
        }
    }

    cout << cnt << endl;
}

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