Cod sursa(job #2214442)

Utilizator AndreiDumitrescuAndrei Dumitrescu AndreiDumitrescu Data 19 iunie 2018 00:32:36
Problema Stramosi Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.25 kb
#include <iostream>
#include <fstream>

using namespace std;

ifstream f("stramosi.in");
ofstream g("stramosi.out");

int n, m;
int dp[30][250010];

int creez_dinamica()
{
    for(int j = 1; j <= 17; j++)
        for(int i = 1; i <= n; i++)
            dp[j][i] = dp[j - 1][dp[j-1][i]];
}

int query(int x, int p)
{
    /*int putere = 1, contor = 0;
    while(putere <= p)
    {
        putere *= 2;
        contor++;
    }
    putere /= 2;
    contor--;
    for(int i = contor; i >= 0 && p ; i--)
    {
        if((1 << i) <= p)
        {
            x = dp[x][i];
            p = p - (1 << i);
        }
    }
    return x;*/
    while(p)
    {
        int putere = 1, contor = 0;
        while(putere <= p)
        {
            putere *= 2;
            contor++;
        }
        putere /= 2;
        contor--;
        if(putere == p)
        {
            return dp[contor][x];
        }

        x = dp[contor][x];
        p = p - putere;
    }
}

int main()
{
    int x, p;
    f >> n >> m;
    for(int i = 1; i <= n; i++)
    {
         f >> dp[0][i];
    }
    creez_dinamica();
    for(int i = 0; i < m; i++)
    {
        f >> x >> p;
        g << query(x, p);
        g << '\n';
    }

}