void merge(Tlist* l, Tlist* m)
{
    int auxval;
    Tnode* currNode1;
    Tnode* currNode2;
    Tlist* auxlist = malloc(sizeof(Tlist));
    list_init(auxlist);
    currNode1 = l -> head;
    currNode2 = m -> head;
    while (currNode1 != NULL && currNode2 != NULL)
    {
        if (currNode1 -> value <= currNode2 -> value)
        {
            auxval = currNode1 -> value;
            insert_tail(auxlist, auxval);
            currNode1 = currNode1 -> next;
        }
        else
        {
            auxval = currNode2 -> value;
            insert_tail(auxlist, auxval);
            currNode2 = currNode2 -> next;
        }
    }
    if (currNode1 == NULL)
    {
        while (currNode2 != NULL)
        {
            auxval = currNode2 -> value;
            insert_tail(auxlist, auxval);
            currNode2 = currNode2 -> next;
        }
    }
    else
        while (currNode1 != NULL)
        {
            auxval = currNode1 -> value;
            insert_tail(auxlist, auxval);
            currNode1 = currNode1 -> next;
        }
    l -> head = auxlist -> head;
    l -> nElements = auxlist -> nElements;
}

void merge_sort(Tlist* l)
{
    int size = size_list(l);
    int index = 1;
    if (size <= 1)
        return;
    Tlist* auxlist1 = malloc(sizeof(Tlist));
    Tlist* auxlist2 = malloc(sizeof(Tlist));
    list_init(auxlist1);
    list_init(auxlist2);
    auxlist1 -> head = l -> head;
    Tnode* currNode;
    currNode = l -> head;
    while (index != size/2)
    {
        currNode = currNode -> next;
        index ++;
    }
    auxlist2 -> head = currNode -> next;
    currNode -> next = NULL;
    auxlist1 -> nElements = size/2;
    auxlist2 -> nElements = size - size/2;
    merge_sort(auxlist1);
    merge_sort(auxlist2);
    merge(auxlist1, auxlist2);
    l -> head = auxlist1 -> head;
}