Problema BiArbore

#include    <iostream>
#include    <fstream>

using namespace std;

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

struct nod
{
    int valoare;
    nod *left, *right;
};

nod *radacina;

void citire(nod *&nodeParam)
{
    nod *newNode = new nod;
    int nr;
    if(fin >> nr && nr != 0)
    {
        // cout << "[!!]: Am citit: " << nr << "\n";
        newNode->valoare = nr;
        newNode->left = NULL;
        newNode->right = NULL;

        if(nodeParam == NULL)
            nodeParam = newNode;

        citire(newNode->left);
        citire(newNode->right);
    }
}

void parcurgere(nod *nodeCrt)
{
    if(nodeCrt != NULL)
    {
        // cout << "Nodul: " << nodeCrt->valoare << "\n";

        // cout << "[!!]: Left Child: ";
        parcurgere(nodeCrt->left);

        // cout << "[!!]: Right Child: ";
        parcurgere(nodeCrt->right);

        // cout << "\n\n";
    }
}

int main()
{
    citire(radacina);
    // parcurgere(radacina);
    fout << radacina->left->valoare << " " << radacina->right->valoare;
    return 0;
}