Cod sursa(job #526494)

Utilizator darrenRares Buhai darren Data 28 ianuarie 2011 15:19:14
Problema Stramosi Scor 80
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.22 kb
#include <fstream>
#include <algorithm>
#include <vector>

using namespace std;

int N, M;
int pos[250002];
vector<int> V[250002], Qs[250002];
pair<int, int> Q[300002];
vector<int> now, rem;
int x, useit;

void Dfs()
{
    now.push_back(x);

    for (int i = 0; i < Qs[x].size(); ++i)
    {
        if (Qs[x][i] > now.size() - 1)
            Qs[x][i] = 0;
        else
            Qs[x][i] = now[now.size() - 1 - Qs[x][i]];
    }

    for (useit = 0; useit < V[x].size(); ++useit)
    {
        rem.push_back(useit);
        x = V[x][useit];

        Dfs();

        useit = rem.back();
        rem.pop_back();
        x = now.back();
    }

    now.pop_back();
}

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

    fin >> N >> M;
    for (int i = 1, aux; i <= N; ++i)
    {
        fin >> aux;
        V[aux].push_back(i);
    }
    for (int i = 1; i <= M; ++i)
    {
        fin >> Q[i].first >> Q[i].second;
        Qs[Q[i].first].push_back(Q[i].second);
    }

    Dfs();

    for (int i = 1; i <= M; ++i)
    {
        fout << Qs[Q[i].first][pos[Q[i].first]] << '\n';
        ++pos[Q[i].first];
    }

    fin.close();
    fout.close();
}