Submission #49985

#	Time	Username	Problem	Language	Result	Execution time	Memory
49985		zetapi	Circle selection (APIO18_circle_selection)	C++14	0 / 100	3067 ms	33816 KiB

circle_selection

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

#define pb  push_back
#define mp  make_pair
#define int long long
#define itr ::iterator 

typedef pair<int,int>  pii;

const int MAX=4e5;
const int INF=1e12;

vector< pair<int,pii> > vec;

set<pii> st;
set<pii> itr it,it2;

int N,ind,X[MAX],Y[MAX],R[MAX],par[MAX];

void ok(int F,int S)
{
	if((X[F]-X[S])*(X[F]-X[S])+(Y[F]-Y[S])*(Y[F]-Y[S])>(R[F]+R[S])*(R[F]+R[S]))
		return ;
	if(R[F]==R[S] and F>S)
		swap(F,S);
	if(R[F]>R[S])
		swap(F,S);
	par[F]=S;
	return ;
}

bool cmp(pair<int,pii> F,pair<int,pii> S)
{
	if(F.first!=S.first)
		return F.first<S.first;
	if(F.second.first!=S.second.first)
		return F.second.first<S.second.first;
	int ind=F.second.second,ind2=S.second.second;
	return X[ind]<X[ind2];
}

signed main()
{
	ios_base::sync_with_stdio(false);
	/*cin.tie(0);
	cout.tie(0);*/

	cin>>N;
	for(int A=1;A<=N;A++)
	{
		par[A]=A;
		cin>>X[A]>>Y[A]>>R[A];
		vec.pb(mp(Y[A]-R[A],mp(0,A)));
		vec.pb(mp(Y[A]+R[A],mp(1,A)));
	}
	sort(vec.begin(),vec.end(),cmp);
	for(int A=0;A<vec.size();A++)
	{
		ind=vec[A].second.second;
		if(vec[A].second.first==0)
		{
			st.insert(mp(X[ind],ind));
			/*it=st.find(mp(X[ind],ind));
          	it++;
			if(it!=st.end())
				ok(ind,it->second);
			it--;
			if(it!=st.begin())
			{
				it--;
				ok(ind,it->second);
			}*/

		}
		else
 		{
 			/*it=st.find(mp(X[ind],ind));
 			it2=it;
 			it2++;
 			if(it2!=st.end() and it!=st.begin())
 			{
 				it--;
 				ok(it->second,it2->second);
 			}*/
 			st.erase(mp(X[ind],ind));	
 		}
 		int pre=0;
		for(auto A:st)
		{
			if(pre)
				ok(pre,A.second);
			pre=A.second;
		}
	}
	for(int A=1;A<=N;A++)
		cout<<par[A]<<" ";
	return 0;
}

Compilation message (stderr)

circle_selection.cpp: In function 'int main()':
circle_selection.cpp:58:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int A=0;A<vec.size();A++)
              ~^~~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 12
• Subtask 3: 0 / 15
• Subtask 4: 0 / 23
• Subtask 5: 0 / 30
• Subtask 6: 0 / 13