Submission #1329893

#	Time	Username	Problem	Language	Result	Execution time	Memory
1329893		Zone_zonee	Collecting Mushrooms (NOI18_collectmushrooms)	C++20	100 / 100	18 ms	25680 KiB

mushrooms

#include <bits/stdc++.h>
using namespace std;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m, sz, k;
    cin >> n >> m >> sz >> k;
    queue<pair<int, int>> q;
    vector<vector<int>> sweep(n+10, vector<int>(m+10, 0));
    for(int i = 1; i <= n; ++i){
        for(int j = 1; j <= m; ++j){
            char c;
            cin >> c;
            if(c == 'M') q.push({i, j});
            if(c == 'S'){
                sweep[max(1, i-sz)][max(1, j-sz)]++;
                sweep[min(n+5, i+sz+1)][min(m+5, j+sz+1)]++;
                sweep[max(1, i-sz)][min(m+5, j+sz+1)]--;
                sweep[min(n+5, i+sz+1)][max(1, j-sz)]--;
            }
        }
    }
    for(int i = 1; i <= n; ++i){
        for(int j = 1; j <= m; ++j){
            sweep[i][j] += sweep[i-1][j] + sweep[i][j-1] - sweep[i-1][j-1];
        }
    }
    int res = 0;
    while(!q.empty()){
        auto [x, y] = q.front(); q.pop();
        if(sweep[x][y] >= k) res++;
    }
    cout << res << '\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