#include <string>
using namespace std;

struct animal {
    int sifra;
    string naziv;
    string vrsta;
    string datum;
    int cijena;    
};

struct List {
    animal a;
    List *next;
};

typedef List Lista;
typedef List* element;

element GRESKA;

void InitL(Lista *list) {
    element novi = new Lista;
    novi->next = NULL;
    list->next = novi;    
}

element FirstL(Lista *list) {
    return list->next;
}

element EndL(Lista *list) {
    element tekuci = list->next;
    while (tekuci->next != NULL) {
        tekuci = tekuci->next;
    }
    return tekuci;
}

element PreviousL(element e, Lista *list) {
    element tekuci = list;

    while (tekuci->next != e) {
        tekuci = tekuci->next;
    }
    return tekuci;
}

int InsertL(animal nova_z, element e, Lista *list) {
    element novi = new Lista;
    novi->a = nova_z;

    novi->next = e;
    element prethodni = PreviousL(e, list);
    prethodni->next = novi;
    return 1;
}

bool DeleteL(element e, Lista *list) {
    
    element tekuci = list;

    while (tekuci->next != e) {
        tekuci = tekuci->next;
    }
    
    tekuci->next = e->next;

    delete e;

    return true;
    
}

void DeleteAll(Lista *list) {
    element tekuci, brisi;

    tekuci = list->next;

    while(tekuci != NULL) {
        brisi = tekuci;
        tekuci = tekuci->next;
        delete brisi;
    }
    
    element zadnji = new Lista;
    zadnji->next = NULL;
    list->next = zadnji;
}

element LocateL(animal odbjegla, Lista *list) {
    element tekuci;
    tekuci = list->next;

    while (tekuci != EndL(list)) {
        if (tekuci->a.sifra == odbjegla.sifra) {
            return tekuci;
        }
        tekuci = tekuci->next;
    }

    return GRESKA;

}

element NextL(element e, Lista *list) {
    return e->next;
}

animal RetrieveL (element e, Lista *list) {
    return e->a;
}

Implementacija liste pomocu pokazivaca

Lista_pokazivaci.h

sort

C++