Submission #623448

#	Time	Username	Problem	Language	Result	Execution time	Memory
623448		hail	Collecting Mushrooms (NOI18_collectmushrooms)	C++17	100 / 100	24 ms	20900 KiB

mushrooms

#include <bits/stdc++.h>
 
using namespace std;
 
#define vi vector<int>
#define vll vector<long long>
#define pb push_back
using ll= long long;
#define fast_io ios::sync_with_stdio(0); cin.tie(0)
#define inpint(x) int x; cin>>x
#define inpll(x) long long x; cin>>x
#define fl(i, n) for(int i=0; i<n; i++)
#define fl_1(i, n) for(int i=1; i<=n; i++)
#define int long long 
#define pi pair<int, int>
#define mp make_pair
#define ld long double



void solve()
{
    int r, c, d, k;
    cin>>r>>c>>d>>k;

    vector<pi> mushrooms(0);

    vector<vector<int>> sp_pre(r+1, vector<int>(c+1, 0));

    for(int i=1; i<=r; i++)
    {
        for(int j=1; j<=c; j++)
        {
            char a;
            cin>>a;

            sp_pre[i][j] = sp_pre[i-1][j] + sp_pre[i][j-1] - sp_pre[i-1][j-1];

            if(a=='M')
            {
                mushrooms.pb(mp(i, j));
            }
            else if(a=='S')
            {
                sp_pre[i][j]++;
            }
        }
    }

    int ans{};

    for(auto i: mushrooms)
    {
        pi tl = mp(max((int)1, i.first-d), max((int)1, i.second-d));
        pi br = mp(min(r, i.first+d), min(c, i.second+d));

        int nmus = sp_pre[br.first][br.second] - sp_pre[tl.first-1][br.second] - sp_pre[br.first][tl.second-1] + sp_pre[tl.first-1][tl.second-1];
        if(nmus>=k) ans++;
    }


    cout<<ans<<"\n";
    
}
 
int32_t main()
{
    fast_io;
 
    int t=1; 
    //cin>>t;
    while(t--)
    {
        solve();
    }
 
}

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