Submission #62494

#	Time	Username	Problem	Language	Result	Execution time	Memory
62494		zetapi	Parachute rings (IOI12_rings)	C++17	100 / 100	2695 ms	97452 KiB

rings

#include <cstdio>
#include <vector>
#include <cassert>
 
 
using namespace std;
 
typedef pair<int,int>  pii;
 
const int MAX=1e6+99;
 
vector<int> vec[MAX];

pii E[MAX];

int linear[4],destruct[4],deg[4][MAX],OtherEnd[4][MAX];
 
int N,M,cnt,CycleSize,Quad,a,b,lol,size_[MAX];

void Init(int N_) 
{
	M=0;
  	N=N_;
  	cnt=0;
  	Quad=0;
  	CycleSize=0;
  	for(int A=0;A<N;A++)
  	{
  		size_[A]=1;
  		deg[0][A]=0;
  		OtherEnd[0][A]=A;
  		vec[A].clear();
  	}
  	return ;
}
 
void Add(int X,int Y)
{
	for(int A=0;A<4;A++) 	
	{
		if(!linear[A] or destruct[A]==X or destruct[A]==Y)
			continue;
		deg[A][X]++;
		deg[A][Y]++;
		if(deg[A][X]==3 or deg[A][Y]==3 or OtherEnd[A][X]==Y)
		{
			linear[A]=0;
			continue;
		}
		a=OtherEnd[A][X];
		b=OtherEnd[A][Y];
		OtherEnd[A][X]=-1;
		OtherEnd[A][Y]=-1;
		OtherEnd[A][a]=b;
		OtherEnd[A][b]=a;
	}
	return ;
}
 
void Split(int X)
{
	Quad=1;
	destruct[0]=X;
	destruct[1]=vec[X][0];
	destruct[2]=vec[X][1];
	destruct[3]=vec[X][2];
	for(int A=0;A<4;A++)
	{
		linear[A]=1;
		for(int B=0;B<N;B++)
		{
			deg[A][B]=0;
			OtherEnd[A][B]=B;
		}
	}
	for(int A=0;A<M;A++)
		Add(E[A].first,E[A].second);
	return ;	
}
 
void Link(int X,int Y) 
{
	E[M++]=make_pair(X,Y);
	if(Quad==0)
	{
		vec[X].push_back(Y);
		vec[Y].push_back(X);
		deg[0][X]++;
		deg[0][Y]++;
		if(deg[0][X]==3)
		{
			Split(X);
			return ;
		}
		if(deg[0][Y]==3)
		{
			Split(Y);
			return ;
		}
		if(OtherEnd[0][X]!=Y)
		{
          	a=OtherEnd[0][X];
			b=OtherEnd[0][Y];
			lol=size_[a];
          	size_[a]=lol+size_[b];
			size_[b]=lol+size_[b];
			OtherEnd[0][X]=-1;
			OtherEnd[0][Y]=-1;
			OtherEnd[0][a]=b;
			OtherEnd[0][b]=a;
			return ;
		}
		cnt++;
		if(cnt==1)
			CycleSize=size_[Y];
	}
	else
		Add(X,Y);
	return ;
}
 
int CountCritical() 
{	
	if(!Quad)
	{
		if(cnt>1)
			return 0;
		else if(CycleSize)
			return CycleSize;
		else
			return N;
	}
	else
		return (linear[0]+linear[1]+linear[2]+linear[3]);
}

• Subtask 1: 20 / 20
• Subtask 2: 17 / 17
• Subtask 3: 18 / 18
• Subtask 4: 14 / 14
• Subtask 5: 31 / 31