Submission #59241

#	Time	Username	Problem	Language	Result	Execution time	Memory
59241		TadijaSebez	Ideal city (IOI12_city)	C++11	100 / 100	617 ms	29024 KiB

city

#include <stdio.h>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;
#define mp make_pair
#define pb push_back
#define ll long long 
const int N=100050;
const int mod=1e9;
int comp[N],cnt;
map<pair<int,int> ,int> id;
vector<int> E[N];
int weg[N],sz[N],n;
int x[N],y[N],p[N];
void init(){ for(int i=0;i<N;i++) p[i]=i;}
int Find(int x){ return x==p[x]?x:p[x]=Find(p[x]);}
void Union(int x, int y){ p[Find(x)]=Find(y);}
int dep[N];
ll ans;
void DFS(int u, int p)
{
	int i;
	//printf("DFS:%i %i\n",u,p);
	sz[u]=weg[u];
	dep[u]=dep[p]+1;
	for(i=0;i<E[u].size();i++)
	{
		int v=E[u][i];
		if(v!=p) DFS(v,u),sz[u]+=sz[v];
	}
	ll mul=0;
	//int sub=0;
	for(i=0;i<E[u].size();i++)
	{
		int v=E[u][i];
		if(v!=p)
		{
			mul+=(ll)sz[v]*(sz[u]-sz[v])%mod;
			mul%=mod;
			//sub+=sz[v];
		}
	}
	mul+=(ll)weg[u]*(weg[u]-1)%mod;
	mul%=mod;
	ans-=(ll)mul*dep[u]%mod;
	if(ans<0) ans+=mod;
	ans+=(ll)(n-sz[u]+weg[u]-1)*weg[u]%mod*dep[u]%mod;
	ans%=mod;
	//printf("u:%i -mul:%lld +mul:%lld weg:%lld sz:%lld\n",u,mul,(n-sz[u]+weg[u]-1)*weg[u],weg[u],sz[u]);
}
int SolveTree()
{
	ans=0;
	DFS(1,0);
	return ans%mod;
}
int DistanceSum(int M, int X[], int Y[])
{
	n=M;
	int i,j;
	for(i=1;i<=n;i++) x[i]=X[i-1],y[i]=Y[i-1];
	for(i=1;i<=n;i++) id[mp(x[i],y[i])]=i;
	for(i=1;i<=n;i++)
	{
		if(!comp[i])
		{
			cnt++;
			comp[i]=cnt;
			weg[cnt]=1;
			j=1;
			while(id.count(mp(x[i],y[i]+j))) comp[id[mp(x[i],y[i]+j)]]=cnt,j++,weg[cnt]++;
			j=1;
			while(id.count(mp(x[i],y[i]-j))) comp[id[mp(x[i],y[i]-j)]]=cnt,j++,weg[cnt]++;
		}
	}
	//for(i=1;i<=n;i++) printf("%i ",comp[i]);printf("\n");
	//for(i=1;i<=cnt;i++) printf("%i ",weg[i]);printf("\n");
	init();
	for(i=1;i<=n;i++)
	{
		int u=id[mp(x[i]+1,y[i])];
		if(u && Find(comp[i])!=Find(comp[u]))
		{
			//printf("(%i - %i)\n",comp[i],comp[u]);
			E[comp[i]].pb(comp[u]);
			E[comp[u]].pb(comp[i]);
			Union(comp[i],comp[u]);
		}
		u=id[mp(x[i]-1,y[i])];
		if(u && Find(comp[i])!=Find(comp[u]))
		{
			//printf("(%i - %i)\n",comp[i],comp[u]);
			E[comp[i]].pb(comp[u]);
			E[comp[u]].pb(comp[i]);
			Union(comp[i],comp[u]);
		}
	}
	int sol=SolveTree();
	//printf("->%i\n",sol);
	for(i=1;i<=n;i++) comp[i]=0;
	for(i=1;i<=cnt;i++) E[i].clear();
	cnt=0;
	for(i=1;i<=n;i++)
	{
		if(!comp[i])
		{
			cnt++;
			comp[i]=cnt;
			weg[cnt]=1;
			j=1;
			while(id[mp(x[i]+j,y[i])]) comp[id[mp(x[i]+j,y[i])]]=cnt,j++,weg[cnt]++;
			j=1;
			while(id[mp(x[i]-j,y[i])]) comp[id[mp(x[i]-j,y[i])]]=cnt,j++,weg[cnt]++;
		}
	}
	//for(i=1;i<=n;i++) printf("%i ",comp[i]);printf("\n");
	init();
	for(i=1;i<=n;i++)
	{
		int u=id[mp(x[i],y[i]+1)];
		if(u && Find(comp[i])!=Find(comp[u]))
		{
			//printf("(%i - %i)\n",comp[i],comp[u]);
			E[comp[i]].pb(comp[u]);
			E[comp[u]].pb(comp[i]);
			Union(comp[i],comp[u]);
		}
		u=id[mp(x[i],y[i]-1)];
		if(u && Find(comp[i])!=Find(comp[u]))
		{
			//printf("(%i - %i)\n",comp[i],comp[u]);
			E[comp[i]].pb(comp[u]);
			E[comp[u]].pb(comp[i]);
			Union(comp[i],comp[u]);
		}
	}
	sol+=SolveTree();
	sol%=mod;
	return sol;
}

Compilation message (stderr)

city.cpp: In function 'void DFS(int, int)':
city.cpp:27:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(i=0;i<E[u].size();i++)
          ~^~~~~~~~~~~~
city.cpp:34:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(i=0;i<E[u].size();i++)
          ~^~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 21 / 21
• Subtask 3: 23 / 23
• Subtask 4: 45 / 45