Cod sursa(job #3363585)

Utilizator RaresPanuPanu Rares RaresPanu Data 19 august 2026 15:54:55
Problema Stramosi Scor 0
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 0.9 kb
#include <fstream>
#include <iostream>

using namespace std;

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

int str[250001][18];

void build(int n) {
    for (int i=1;i<=17;i++) {
        for (int j=1;j<=n;j++) {
            if (str[j][i-1]==0) {
                str[j][j]=0;
            }else {
                str[j][i]=str[str[j][i-1]][i-1];
            }
        }
    }
}

int main(){
    int n,q;
    fin>>n>>q;
    for (int i=1;i<=n;i++) {
        fin >> str[i][0];
    }
    build(n);
    for (int i=1;i<=q;i++) {
        int a,b;
        fin >> a >> b;
        int rez=-1;
        int bit=0;
        while ((1<<bit)<=b) {
            if ((b>>bit)&1) {
                if (rez==-1) {
                    rez=str[a][bit];
                }else {
                    rez=str[rez][bit];
                }
            }
            bit++;
        }
        fout << rez << "\n";
    }
    return 0;
}