Submission #925617

#	Time	Username	Problem	Language	Result	Execution time	Memory
925617		vjudge1	Collecting Mushrooms (NOI18_collectmushrooms)	C++17	79 / 100	2021 ms	2908 KiB

mushrooms

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define ll long long
#define pb push_back
#define emb emplace_back
#define emc emplace
#define pii pair<int,int>
#define pll pair<ll,ll>
#define F first
#define S second
template <class type_key, class type_val>
using um = unordered_map<type_key, type_val>;
template <class T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template <class T>
using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;

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

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

	if( n == 1 ) {
		int msh = 0;
		int spr = 0;

		vector<int> cnt(m+1, 0);
		char c[m+1];
		for( int i = 1; i <= m; i++ ) {
			cin >> c[i];
			if( c[i] == 'S') {
				cnt[max(i-d,1)]++;
				if( i+d+1 <= m ) cnt[i+d+1]--;
			}
		}
		int ans = 0;
		for( int i = 1; i <= m; i++ ) {
			spr += cnt[i];
			if( c[i] == 'M') {
				if( spr >= k ) ans++;
			}
		}
		cout << ans;

		return 0;
	} else {
		vector<pii> msh;
		vector<pii> spr;
		for( int i = 1; i <= n; i++ ) {
			for( int j = 1; j <= m; j++ ) {
				char c; cin >> c;
				if( c == 'M') msh.emb(i,j);
				if( c == 'S') spr.emb(i,j);
			}
		}
		sort(spr.begin(), spr.end());

		int ans = 0;
		for( int i = 0; i < msh.size(); i++ ) {
			int cnt = 0;
			if( spr.size() > 0 ) {
				int pos = lower_bound(spr.begin(), spr.end(), make_pair(msh[i].F-d, msh[i].S-d)) - spr.begin();
				if( pos >= 0 && pos < spr.size() ) {
					if( (spr[pos].F - msh[i].F) > d ) pos++;
					for( int j = pos; j < spr.size(); j++ ) {
						if( abs(msh[i].F - spr[j].F) > d ) break;
						if( abs(msh[i].S - spr[j].S) <= d ) cnt++;
						if( cnt >= k ) break;
					}
					if( cnt >= k ) {
						ans++;
					}
				}
			}
		}
		cout << ans;
	}

return 0;
}

Compilation message (stderr)

mushrooms.cpp: In function 'int main()':
mushrooms.cpp:31:7: warning: unused variable 'msh' [-Wunused-variable]
   31 |   int msh = 0;
      |       ^~~
mushrooms.cpp:66:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   66 |   for( int i = 0; i < msh.size(); i++ ) {
      |                   ~~^~~~~~~~~~~~
mushrooms.cpp:70:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   70 |     if( pos >= 0 && pos < spr.size() ) {
      |                     ~~~~^~~~~~~~~~~~
mushrooms.cpp:72:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |      for( int j = pos; j < spr.size(); j++ ) {
      |                        ~~^~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 10 / 10
• Subtask 3: 18 / 18
• Subtask 4: 23 / 23
• Subtask 5: 19 / 19
• Subtask 6: 0 / 21