Cod sursa(job #2877790)

Utilizator alexmorosanuMorosanu Alexandru alexmorosanu Data 25 martie 2022 12:43:43
Problema Stramosi Scor 80
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.98 kb
#include <fstream>
#include <vector>
using namespace std;
ifstream f("stramosi.in");
ofstream g("stramosi.out");
vector <int> stramos[250011],v[250011];
int lg[250011],lev[250011];
void stramosi_build(int k,int lvl)
{
    lev[k]=lvl;
    for(int i=1;i<=lg[lvl];i++)
        stramos[k].push_back(stramos[stramos[k][i-1]][i-1]);
    for(int i=0;i<v[k].size();i++)
        stramosi_build(v[k][i],lvl+1);
}
int n,m,i,x,p,l,k;
int main()
{
    f>>n>>m;
    for(i=2;i<=n;i++)
        lg[i]=lg[i/2]+1;
    for(i=1;i<=n;i++)
    {
        f>>x;
        v[x].push_back(i);
        stramos[i].push_back(x);
    }
    stramosi_build(0,0);
    for(i=1;i<=m;i++)
    {
        f>>l>>p;
        if(p>lev[l])
        {
            g<<0<<'\n';
            continue;
        }
        k=0;
        while(p>0 && l>0)
        {
            if(p%2==1)
                l=stramos[l][k];
            p=p/2;
            k++;
        }
        g<<l<<'\n';
    }
    return 0;
}