Cod sursa(job #1791050)

Utilizator GeanaVladGeana Vlad GeanaVlad Data 29 octombrie 2016 00:04:12
Problema Stramosi Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.92 kb
#include <iostream>
#include<fstream>
using namespace std;
ifstream f("stramosi.in");
ofstream g("stramosi.out");
int n,q,i,v[250001],log2[20],p,k,r[250001][20],p2,j;
inline void BuildRMQ()
{
    int m=log2[n]+1,i,j;
    for(i=1; i<=n; i++)
        r[i][0]=v[i];
    for(j=1; j<m; j++)
        for(i=1; i<=n; i++)
            r[i][j]=r[r[i][j-1]][j-1];
}
inline int functie(int p,int k)
{
    while(k && p)
    {
        bool ok=1;
        for(int i=log2[k]+1; i>=0 && ok; i--)
            if(k&(1<<i))
            {
                ok=0;
                p=r[p][log2[k]];
                k-=(1<<i);
            }
    }
    return p;
}
int main()
{
    f>>n>>q;
    for(i=1; i<=n; i++)
        f>>v[i];
    log2[1]=0;
    for(i=2; i<=n; i++)
        log2[i]=log2[i/2]+1;
    BuildRMQ();
    for(; q; q--)
    {
        f>>p>>k;//al k lea stramos al lui p
        g<<functie(p,k)<<'\n';
    }
}