Submission #115380

#	Time	Username	Problem	Language	Result	Execution time	Memory
115380		faustaadp	Friend (IOI14_friend)	C++17	69 / 100	68 ms	31324 KiB

friend

#include "friend.h"
#include<bits/stdc++.h>
typedef long long ll;
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
// Find out best sample
ll i,n,b[3],a[101010],jum,ma,x[2],has,j,k;
vector<ll> v[101010];
ll vis[101010];
ll mat[101010];
ll d[101010][2];
ll udh[1010][1010];
ll ada[1010];
ll z[101010];
ll dfs(ll aa)
{
	if(vis[aa])
		return 0;
	vis[aa]=1;
	ll ii;
	for(ii=0;ii<v[aa].size();ii++)
		if(mat[v[aa][ii]]==-1||dfs(mat[v[aa][ii]]))
		{
			mat[v[aa][ii]]=aa;
			return 1;
		}
	return 0;
}
ll depe(ll aa,ll bb,ll cc)
{
	if(d[aa][bb]==-1)
	{
		ll ii,h1=a[aa],h2=0;
		for(ii=0;ii<v[aa].size();ii++)
		{
			if(v[aa][ii]==cc)continue;
			h1+=depe(v[aa][ii],1,aa);
			h2+=depe(v[aa][ii],0,aa);
		}
		d[aa][bb]=max(h1,h2);
		if(bb)
			d[aa][bb]=h2;
	}
	return d[aa][bb];
}
void dfs2(ll aa,ll bb)
{
	if(vis[aa])return ;
	z[aa]=bb;
	vis[aa]=1;
	ll ii;
	for(ii=0;ii<v[aa].size();ii++)
		dfs2(v[aa][ii],1-bb);
}
int findSample(int n,int confidence[],int host[],int protocol[])
{
	//int ans=10;
	for(i=1;i<n;i++)
		b[protocol[i]]=1;
	for(i=0;i<n;i++)
	{
		if(i>=1&&(!(b[0]==0&&b[1]==0&&b[2]==1)))
		{
			if(protocol[i]==0)
			{
				if(!udh[host[i]][i])
				{		
					v[host[i]].pb(i);
					v[i].pb(host[i]);
				//	cout<<i<<"  "<<i<<" "<<host[i]<<"\n";
					udh[i][host[i]]=1;
					udh[host[i]][i]=1;
				}
			}
			else
			if(protocol[i]==1)
			{
				for(j=0;j<v[host[i]].size();j++)
				{
					if(udh[i][v[host[i]][j]])continue;
			//		cout<<i<<"  "<<v[host[i]][j]<<" "<<i<<"\n";
					v[v[host[i]][j]].pb(i);
					v[i].pb(v[host[i]][j]);
					udh[i][v[host[i]][j]]=1;
					udh[v[host[i]][j]][i]=1;
				}
			}
			else
			//if(n<=10)
			{
				for(j=0;j<v[host[i]].size();j++)
				{
					if(udh[i][v[host[i]][j]])continue;
			//		cout<<i<<"  "<<v[host[i]][j]<<" "<<i<<"\n";
					v[v[host[i]][j]].pb(i);
					v[i].pb(v[host[i]][j]);
					udh[i][v[host[i]][j]]=1;
					udh[v[host[i]][j]][i]=1;
				}
				if(!udh[host[i]][i])
				{		
					v[host[i]].pb(i);
					v[i].pb(host[i]);
				//	cout<<i<<"  "<<i<<" "<<host[i]<<"\n";
					udh[i][host[i]]=1;
					udh[host[i]][i]=1;
				}
			}
		}
		a[i]=confidence[i];
		jum+=a[i];
		ma=max(ma,a[i]);
	}
	if(b[0]==0&&b[1]==1&&b[2]==0)
		return jum;
	if(b[0]==0&&b[1]==0&&b[2]==1)
		return ma;
	if(b[0]==1&&b[1]==0&&b[2]==0)
	{
		memset(d,-1,sizeof(d));
		return depe(0,0,0);
	}
	if(n<=10)
	{
		for(i=0;i<(1<<n);i++)
		{
			ll hz=0;
			for(j=0;j<n;j++)
				if(i&(1<<j))
				{
					hz+=a[j];
					ada[j]=1;
				}
				else
					ada[j]=0;
			for(j=0;j<n;j++)
				for(k=0;k<v[j].size();k++)
					if(ada[j]&&ada[v[j][k]])
					{
				//		cout<<i<<" "<<j<<" "<<v[j][k]<<"\n";
						hz=0;
						break;
					}
			has=max(has,hz);
		}
		return has;
	}
	if(b[0]==1&&b[1]==1&&b[2]==0)
	{
		memset(mat,-1,sizeof(mat));
	//	has=n;
		for(i=0;i<n;i++)
			dfs2(i,0);
		for(i=0;i<n;i++)
		{
			memset(vis,0,sizeof(vis));
			if(z[i]==0)
				has+=dfs(i);
		//	cout<<i<<" "<<has<<"\n";
		//	if(v[i].empty())
		//		has++;
		}
		has=n-has;
		return has;
	}
}

Compilation message (stderr)

friend.cpp: In function 'll dfs(ll)':
friend.cpp:24:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(ii=0;ii<v[aa].size();ii++)
           ~~^~~~~~~~~~~~~
friend.cpp: In function 'll depe(ll, ll, ll)':
friend.cpp:37:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(ii=0;ii<v[aa].size();ii++)
            ~~^~~~~~~~~~~~~
friend.cpp: In function 'void dfs2(ll, ll)':
friend.cpp:55:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(ii=0;ii<v[aa].size();ii++)
           ~~^~~~~~~~~~~~~
friend.cpp: In function 'int findSample(int, int*, int*, int*)':
friend.cpp:81:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(j=0;j<v[host[i]].size();j++)
             ~^~~~~~~~~~~~~~~~~~
friend.cpp:94:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(j=0;j<v[host[i]].size();j++)
             ~^~~~~~~~~~~~~~~~~~
friend.cpp:140:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(k=0;k<v[j].size();k++)
             ~^~~~~~~~~~~~
friend.cpp:169:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

• Subtask 1: 11 / 11
• Subtask 2: 8 / 8
• Subtask 3: 8 / 8
• Subtask 4: 19 / 19
• Subtask 5: 23 / 23
• Subtask 6: 0 / 31