L

#include <iostream>

using namespace std;

struct Nod
{
    int info;
    Nod *leg;
};

struct Lista                            /// Simplu inlantuita
{
    Nod *L;
    void Inserare1(int x)               /// Inserare la inceput
    {
        Nod *p;
        p = new Nod;
        p -> info = x;
        p -> leg = L;
        L = p;
    }

    void Inserare2(Nod *p, int x)       /// Inserare dupa nodul de adresa memorata in p
    {
        Nod *q;
        q = new Nod;
        q -> info = x;
        q -> leg = p -> leg;
        p -> leg = q;
    }

    ///     Insereaza dupa al k-lea nod
    /// un nou nod cu informatia x;
    /// Daca lista are mai putin de
    /// k noduri, inserarea se face
    /// la sfarsitul listei.
    void Inserare3(int k, int x)
    {
        Nod *p, *q;
        for(p = L; (k > 1) && (p != NULL); p = p -> leg)
        {
            k--;
            q = p;
        }
        if(p == NULL) /// Inserez dupa q
            Inserare2(q, x);
        else /// Inserez dupa p
            Inserare2(p, x);
    }

    void Parcurgere()                   /// Parcurgerea listei
    {
        for(Nod *p = L; p != NULL; p = p -> leg)
            cout << p -> info << " ";
        cout << "\n";
    }

    void Init()                         /// Initializarea listei vide
    {
        L = NULL;
    }

    void Sterge1()                      /// Stergerea primului nod
    {
        if(L = NULL) return;
        Nod *p;
        p = L;
        L = p -> leg;
        delete p;
    }

    void Sterge2(Nod *p)                /// Stergerea nodului dupa nodul de adresa memorata p
    {
        Nod *q;
        q = p -> leg;
        p -> leg = q -> leg;
        delete q;
    }

    Nod *Cautare(int x)                 /// Cautarea valorii x in lista si returnarea pointer-ului
    {
        Nod *p;
        for(p = L; p != NULL; p = p -> leg)
            if(p -> info == x)
                return p;
        return NULL;
    }

    void ParcDS(Nod *p) /// Parcurgerea de la dreapta la stanga a nodurilor listei
    {
        if(p != NULL)
        {
            ParcDS(p -> leg);
            cout << p -> info << " ";
        }
    }
};

int main()
{
    Lista w;
    w.Init();

    for(int i = 20; i >= 1; i--)
        w.Inserare1(i);
    w.Parcurgere(); cout << "\n";

    w.Inserare3(300, 100);
    w.Parcurgere();
    cout << w.Cautare(15) -> info << "\n";

    w.ParcDS(w.L); cout << "\n";
    return 0;
}