Submission #50144

#	Time	Username	Problem	Language	Result	Execution time	Memory
50144		zetapi	Circle selection (APIO18_circle_selection)	C++14	100 / 100	1660 ms	26368 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=5e5;

int N,x_,y_,r_,R_cur,R_next,order[MAX],par[MAX];

struct circle
{
	int X;
	int Y;
	int R;
	int ind;
	void init(int X_,int Y_,int R_,int ind_)
	{
		X=X_;
		Y=Y_;
		R=R_;
		ind=ind_;
	}
} 	arr[MAX],lol[MAX];

bool operator<(circle F,circle S)
{
	if(F.X==S.X)
		return F.Y<S.Y;
	return F.X<S.X;
}  

bool cmp(int F,int S)
{
	if(lol[F].R==lol[S].R)
		return lol[F].ind<lol[S].ind;
	return lol[F].R>lol[S].R;
}

bool ok(int F,int S)
{
	return (lol[F].X-lol[S].X)*(lol[F].X-lol[S].X)+(lol[F].Y-lol[S].Y)*(lol[F].Y-lol[S].Y)<=(lol[F].R+lol[S].R)*(lol[F].R+lol[S].R);
}

void init_()
{
	R_cur=R_next;
	R_next/=2;
	for(int A=1;A<=N;A++)
		arr[A].init(lol[A].X/R_cur,lol[A].Y/R_cur,lol[A].R,A);
	sort(arr+1,arr+N+1);
	return ;
}

void solve(int ind)
{
	int tem;
	int pos_x=lol[ind].X/R_cur;
	int pos_y=lol[ind].Y/R_cur;
	par[ind]=ind;
	for(int cur_x=pos_x-2;cur_x<=pos_x+2;cur_x++)
	{
		tem=lower_bound(arr+1,arr+N+1,(circle){cur_x,pos_y-2,0,0})-arr;
		while(tem<=N and arr[tem].X==cur_x and arr[tem].Y<=pos_y+2)
		{
			//cout<<arr[tem].ind<<" "<<ind<<"\n";
			if(par[arr[tem].ind])
			{
				tem++;
				continue;
			}
			else if(ok(ind,arr[tem].ind))
			{
				//cout<<ind<<" "<<arr[tem].ind<<"fu \n";
				par[arr[tem].ind]=ind;
			}
			tem++;
		}
	}
	return ;
}

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

	/* 	input
 		11
		9 9 2
		13 2 1
		11 8 2
		3 3 2
		3 12 1
		12 14 1
		9 8 5
		2 8 2
		5 2 1
		14 4 2
		14 14 1
	*/
	cin>>N;
	for(int A=1;A<=N;A++)
	{
		cin>>x_>>y_>>r_;
		order[A]=A;
		lol[A].init(x_,y_,r_,A);
		R_cur=max(R_cur,lol[A].R);
	}
	R_next=R_cur;
	init_();
	sort(order+1,order+N+1,cmp);
	for(int A=1;A<=N;A++)
	{
		if(par[order[A]])
			continue;
		if(lol[order[A]].R<=R_next)
			init_();
		solve(order[A]);
	}
	for(int A=1;A<=N;A++)
		cout<<par[A]<<" ";
	return 0;
}

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