Cod sursa(job #2491485)

Utilizator PatrickCplusplusPatrick Kristian Ondreovici PatrickCplusplus Data 12 noiembrie 2019 17:44:38
Problema Stramosi Scor 80
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.02 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("stramosi.in");
ofstream fout("stramosi.out");

int n, m, x, y, dp[250005][20], logg[250005], poww[20];

int main()
{
    fin >> n >> m;
    for (int i = 1; i <= n; ++i)
    {
        int nod;
        fin >> nod;
        dp[i][0] = nod;
        if (i == 1)
        {
            continue;
        }
        logg[i] = 1 + logg[i / 2];
    }
    for (int i = 0; i <= 18; ++i)
    {
        poww[i] = (1 << i);
    }
    for (int j = 1; poww[j] <= n; ++j)
    {
        for (int i = 1; i <= n; ++i)
        {
            dp[i][j] = dp[dp[i][j - 1]][j - 1];
        }
    }
    while (m--)
    {
        fin >> x >> y;
        int sol = 0;
        for (int i = logg[y]; i >= 0; --i)
        {
            if (poww[i] & y)
            {
                sol = dp[x][i];
                x = sol;
                y = y - poww[i];
            }
        }
        fout << sol << "\n";
    }
    fin.close();
    fout.close();
    return 0;
}