Cod sursa(job #2283140)

Utilizator TooHappyMarchitan Teodor TooHappy Data 15 noiembrie 2018 00:33:11
Problema Stramosi Scor 80
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.9 kb
#include <bits/stdc++.h>
 
using namespace std;
 
ifstream in("stramosi.in");
ofstream out("stramosi.out");

const int Nmax = 250000;

int n, m, stramos[Nmax + 5][20]; // stramosul lui i de ordin 2^j

int main() {
    ios::sync_with_stdio(false); in.tie(0); out.tie(0);

    in >> n >> m;

    for(int i = 1; i <= n; ++i) {
        in >> stramos[i][0];
    }

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

    while(m--) {
        int q, p; in >> q >> p;

        while(p) {
            int k = log2(p);
            q = stramos[q][k];
            p -= (1 << k);
        }

        // for(int i = 0; (1 << i) <= n && q; ++i) {
        //     if((p >> i) % 2 == 1) {
        //         q = stramos[q][i];
        //     }
        // }
        out << q << "\n";
    }

    in.close(); out.close();
 
    return 0;
}