Cod sursa(job #766150)

Utilizator dutzulBodnariuc Dan Alexandru dutzul Data 10 iulie 2012 14:31:45
Problema Stramosi Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.13 kb
#include<fstream>
#define LE 250500
#include <algorithm>
using namespace std;
ifstream f("stramosi.in");
ofstream g("stramosi.out");
int father[LE],prev[LE],j,n,q,level,M[LE][20],viz[LE],i,nod,two[30],le[LE],levg,leev,lev_ned,random[LE];

void query()
{
	for(j=le[nod];j>=0;--j)
		if (M[nod][j]&&two[j]<=lev_ned)
			nod=M[nod][j],lev_ned-=two[j],query();
}
void setM(int pos)
{
	prev[father[pos]]=pos;
	
	if (prev[pos]!=0)
	{
	  	for(j=0;j<=le[prev[pos]]&&M[prev[pos]][j]!=0;++j) 
			M[pos][j]=father[M[prev[pos]][j]];
	
	return;  
	}
      
	int lev_need=1,lev=0,k=pos,pe=0;

	while (father[k]!=0)
		{
		   ++lev;
		   k=father[k];
	 	   
		   if (lev==lev_need) 
			   M[pos][pe++]=k,lev_need*=2,le[pos]=pe-1;		   
	    } 
}
int main()
{
	f>>n>>q;
	for(i=1;i<=n;++i)
		f>>father[i];
two[0]=1;
for(i=1;i<=22;++i) 
	two[i]=two[i-1]*2;

	for(i=1;i<=n;++i) random[i]=i;
	random_shuffle(random+1,random+n+1);

		for(i=1;i<=n;++i)
       if (viz[random[i]]!=-1)
	     setM(random[i]);
	
	for(i=1;i<=q;++i) 
	{
		f>>nod>>lev_ned;
		query();
		if (lev_ned!=0) g<<0<<'\n'; else 
g<<nod<<'\n';
	}
	return 0;
}