Nan Mihai - Structuri de date (liste simplu inlantuite)

#include <stdio.h>
#include <stdlib.h>

typedef struct Element
{
    int val;
    struct Element* next;
}Element;

typedef Element* List;

List init(int val)
{
    List lista;
    lista = (Element *) malloc(sizeof(Element));
    lista->val = val;
    lista->next = NULL;
    return lista;
}

/*
//recursiv
List append(List l, int val)
{
    List temp, aux;
    aux = l;
    temp = (Element *) malloc(sizeof(Element));
    temp->val = val;
    temp->next = NULL;
    if(aux != NULL)
    {
        aux=aux->next;
        return append(aux, val);
    }
    if(aux == NULL)
    {
        aux->next = temp;
        return l;
    }
}*/




List append(List l, int val)
{
    List aux;
    if(l == NULL)
    {
        aux = (Element *) malloc(sizeof(Element));
        aux->val = val;
        aux->next = NULL;
        return aux;
    }
    else
    {
        if(l->next==NULL)
        {
            l->next=init(val);
            return l;
        }
        else
        {
            l->next = append(l->next, val);
            return l;
        }
    }
}


//recursiv
/*void print(List l)
{
    if(l != NULL)
    {
        printf("%d ", l->val);
        l = l->next;
        print(l);
    }
    else
    {
        printf("\n");
    }
}*/

//iterativ
void print(List l)
{
    while(l != NULL)
    {
        printf("%d ", l->val);
        l = l->next;
    }
    printf("\n");
}

int len(List l)
{
    if(l == NULL)
        return 0;
    else
    {
        l=l->next;
        return 1+len(l);
    }
}

List prepend(List l, int val)
{
    List temp;
    temp = (Element *) malloc(sizeof(Element));
    temp->val = val;
    temp->next = l;
    l = temp;
    return l;
}

List delLast(List l)
{
    List temp;
    temp = l;
    while(temp->next->next != NULL)
    {
        temp = temp->next;
    }
    temp->next = NULL;
    return l;
}

List delFirst(List l)
{
    if(l != NULL)
    {
        l=l->next;
    }
    else
    {
        l = NULL;
    }
    return l;
}

int ultimulElement(List l)
{
    int ultim;
    while(l->next != NULL)
    {
        l = l->next;
    }
    ultim = l->val;
    return ultim;
}

List insert(List l, int val)
{
    int ult;
    Element *p1, *p2, *p;
    if(l == NULL)
    {
        l = (Element *) malloc(sizeof(Element));
        l->val = val;
        l->next = NULL;
        return l;
    }
    else
    {
        ult = ultimulElement(l);
        if(ult <= val)
        {
            l = append(l, val);
        }
        else
        {

                p1 = NULL;
                p2 = l;
            for( ; p2->val < val; p2 = p2->next)
                {
                    p1 = p2;
                if(p2->next->next == NULL)
                    {
                            p2 = p2->next;
                    break;
                    }
                }
                p = (Element *)malloc(sizeof(Element));
            p->val = val;
            p->next = p2;
            if (p1 == NULL)
                        l = p;
            else
                    p1->next = p;
            return l;
        }
    }
}



List freeList(List l)
{
    List tmp;

    while (l != NULL)
        {
           tmp = l;
           l = l->next;
           free(tmp);
        }
    return l;
}

int main()
{
    int dim, ultim;
    List l;
    l = NULL;
    int n;
    l = init(-9);
    print(l);
    scanf("%d", &n);
    while (n!= 0) {
        l = prepend(l, n);
        scanf("%d", &n);
    }
    print(l);
    dim = len(l);
    printf("Dimensiunea listei este %d!\n", dim);
    printf("Eliminare ultimul!\n");
    l = delLast(l);
    print(l);
    printf("Eliminare primul!\n");
    l = delFirst(l);
    print(l);
    printf("Adaugare la sfarsit!\n");
    l = append(l, 10);
    print(l);
    printf("Ultimul element!\n");
    ultim = ultimulElement(l);
    printf("Ultimul element este %d!\n", ultim);
    printf("Inserare element!\n");
    l = insert(l, 55);
    print(l);
    return 0;
}