Cod sursa(job #1630654)

Utilizator DenisONIcBanu Denis Andrei DenisONIc Data 5 martie 2016 10:39:08
Problema Stramosi Scor 80
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.8 kb
#include <fstream>
#include <cstdio>
using namespace std;

ofstream g("stramosi.out");

long n,m,i,j,p,nr,q,dp[250005][30];


long stramos(long q,long p)
{
    long P=1,nr=0;
    if (q==0)
        return 0;
    while (P<<1<=p)
    {
        P<<=1;
        nr++;
    }
    if (P==p)
        return dp[q][nr];
    return stramos(dp[q][nr],p-P);
}

int main()
{
    freopen("stramosi.in","r",stdin);
    scanf("%ld%ld",&n,&m);
    for (i=1;i<=n;i++)
        scanf("%ld",&dp[i][0]);

    p=1;
    while (p<<1<=n)
    {
        p<<=1;
        nr++;
    }

    p=0;

    for (j=1;j<=nr;j++)
        for (i=1;i<=n;i++)
            dp[i][j]=dp[dp[i][j-1]][j-1];

    for (i=1;i<=m;i++)
    {
        scanf("%ld%ld",&q,&p);
        g<<stramos(q,p)<<'\n';
    }
    return 0;
}