Lista jednokierunkowa - jak zmienić funkcję

Question

Cześć 

Mam pytanie jak zmodyfikować ten program, tak aby do funkcji insert_node() i delete_node() początek listy był przekazywany przez parametr będący podwójnym wskaźnikiem, oraz żeby zwracały one wartość typu bool, sygnalizującą poprawność wykonanej operacji. 

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
struct sll_node
{
    int data ;
    struct sll_node * next ;
};

struct sll_node * create_list ( int data )
{
    struct sll_node * front = ( struct sll_node *)
                              malloc ( sizeof ( struct sll_node ) ) ;
    if ( NULL != front )
    {
        front -> data = data ;
        front -> next = NULL ;
    }
    return front ;
}

struct sll_node * insert_front ( struct sll_node *front,
                                 struct sll_node * new_node )
{
    new_node -> next = front ;
    return new_node ;
}

struct sll_node * find_spot ( struct sll_node *front, int data )
{
    struct sll_node * prev = NULL ;
    while (( NULL != front ) && (front -> data > data ) )
    {
        prev = front ;
        front = front -> next ;
    }
    return prev ;

}

void insert_after ( struct sll_node *node, struct sll_node * new_node )
{
    new_node -> next = node -> next ;
    node -> next = new_node ;
}

void insert_back ( struct sll_node *back, struct sll_node * new_node )
{
    back -> next = new_node ;
}

struct sll_node *insert_node ( struct sll_node *front, int data )
{
    if ( NULL == front )
        return NULL ;

    struct sll_node * new_node = ( struct sll_node *)
                                 malloc ( sizeof ( struct sll_node ) ) ;
    if ( NULL != new_node )
    {
        new_node -> data = data ;
        new_node -> next = NULL ;
        if (front -> data <= data )
            return insert_front (front, new_node ) ;
        else
        {
            struct sll_node * node = find_spot (front, data ) ;
            if ( NULL != node -> next )
                insert_after (node, new_node ) ;
            else
                insert_back (node, new_node ) ;
        }
    }
    return front ;
}

struct sll_node * delete_front ( struct sll_node * front )
{


    struct sll_node * next = front -> next ;
    free ( front ) ;
    return next ;
}

struct sll_node * find_prev_node ( struct sll_node *front, int data )
{
    struct sll_node * prev = NULL ;
    while (( NULL != front ) && (front -> data != data ) )
    {
        prev = front ;
        front = front -> next ;
    }
    return prev ;
}

void delete_after ( struct sll_node * node )
{

    struct sll_node * next = node -> next ;
    if ( NULL != next )
    {
        node -> next = next -> next ;
        free ( next ) ;
    }

}

struct sll_node * delete_node ( struct sll_node *front, int data )
{
    if ( NULL == front )
        return NULL ;

    if (front -> data == data )
        return delete_front ( front ) ;

    struct sll_node * prev = find_prev_node (front, data ) ;
    delete_after ( prev ) ;
    return front ;
}

void print_list ( struct sll_node * front )
{
    for (; NULL != front ; front = front -> next )
        printf ("%d ", front -> data ) ;
    printf ("\n") ;
}

void remove_list ( struct sll_node ** front )
{
    struct sll_node * next = NULL ;
    while ( NULL != * front )
    {
        next = (* front ) ->next ;
        free (* front ) ;
        * front = next ;
    }
}

int main ()
{
    struct sll_node * front = create_list (1) ;
    int i;

    for (i=2; i <5; i++)
        front = insert_node (front, i) ;
    for (i=6; i <10; i++)
        front = insert_node (front, i) ;
    printf (" List elements :\n") ;
    print_list ( front ) ;

    front = insert_node (front, 0) ;
    printf (" List elements after insertion of 0:\n") ;
    print_list ( front ) ;
    front = insert_node (front, 5) ;
    printf (" List elements after insertion of 5:\n") ;
    print_list ( front ) ;

    front = insert_node (front, 7) ;
    printf (" List elements after insertion of 7:\n") ;
    print_list ( front ) ;
    front = insert_node (front, 10) ;
    printf (" List elements after insertion of 10:\n") ;
    print_list ( front ) ;

    front = delete_node (front, 0) ;
    printf (" List elements after deletion of 0:\n") ;
    print_list ( front ) ;
    front = delete_node (front, 1) ;
    printf (" List elements after deletion of 1:\n") ;
    print_list ( front ) ;
    front = delete_node (front, 1) ;
    printf (" List elements after deletion of 1:\n") ;
    print_list ( front ) ;
    front = delete_node (front, 5) ;
    printf (" List elements after deletion of 5:\n") ;
    print_list ( front ) ;
    front = delete_node (front, 10) ;
    printf (" List elements after deletion of 10: \n") ;
    print_list ( front ) ;

    remove_list (& front ) ;
    return 0;
}

 

Comments

Proszę, na sam początek sformatuj jakiś ładnie kod. Chodzi o wcięcia. To nie jest ksiażka która się tak o czyta.

---

Proszę

---

Kod jest dosyć dobrze napisany. Ciężko uwierzyć, że ktoś kto napisał ten kod nie potrafi zrobić w nim takiej wręcz kosmetycznej zmiany :P

---

Nie do końca jest tak, że ja napisałem ten kod :P. Po prostu jestem ciekawy jak to zrobić

Answer 1

Pisane na szybko, bo to kosmetyczna podmiana, wynik się zgadza, nie zagłębiałem się ;P
 

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
struct sll_node
{
	int data;
	struct sll_node * next;
};

struct sll_node * create_list(int data)
{
	struct sll_node * front = (struct sll_node *)
		malloc(sizeof(struct sll_node));
	if (NULL != front)
	{
		front->data = data;
		front->next = NULL;
	}
	return front;
}

struct sll_node * insert_front(struct sll_node *front,
	struct sll_node * new_node)
{
	new_node->next = front;
	return new_node;
}

struct sll_node * find_spot(struct sll_node *front, int data)
{
	struct sll_node * prev = NULL;
	while ((NULL != front) && (front->data > data))
	{
		prev = front;
		front = front->next;
	}
	return prev;

}

void insert_after(struct sll_node *node, struct sll_node * new_node)
{
	new_node->next = node->next;
	node->next = new_node;
}

void insert_back(struct sll_node *back, struct sll_node * new_node)
{
	back->next = new_node;
}

bool insert_node(struct sll_node **front, int data)
{
	if (NULL == front)
		return false;

	struct sll_node * new_node = (struct sll_node *)
		malloc(sizeof(struct sll_node));
	if (NULL != new_node)
	{
		new_node->data = data;
		new_node->next = NULL;
		if ((*front)->data <= data)
			*front = insert_front(*front, new_node);
		else
		{
			struct sll_node * node = find_spot(*front, data);
			if (NULL != node->next)
				insert_after(node, new_node);
			else
				insert_back(node, new_node);
		}
		return true;
	}
	else 
		return false;
}

struct sll_node * delete_front(struct sll_node * front)
{
	struct sll_node * next = front->next;
	free(front);
	return next;
}

struct sll_node * find_prev_node(struct sll_node *front, int data)
{
	struct sll_node * prev = NULL;
	while ((NULL != front) && (front->data != data))
	{
		prev = front;
		front = front->next;
	}
	return prev;
}

void delete_after(struct sll_node * node)
{

	struct sll_node * next = node->next;
	if (NULL != next)
	{
		node->next = next->next;
		free(next);
	}

}

bool delete_node(struct sll_node **front, int data)
{
	if (NULL == front)
		return false;

	if ((*front)->data == data) 
	{
		*front = delete_front(*front);
		return true;
	}
	struct sll_node * prev = find_prev_node(*front, data);
	delete_after(prev);
	return true;
}

void print_list(struct sll_node * front)
{
	for (; NULL != front; front = front->next)
		printf("%d ", front->data);
	printf("\n");
}

void remove_list(struct sll_node ** front)
{
	struct sll_node * next = NULL;
	while (NULL != *front)
	{
		next = (*front)->next;
		free(*front);
		*front = next;
	}
}

int main()
{
	struct sll_node * front = create_list(1);
	int i;

	for (i = 2; i <5; i++)
		insert_node(&front, i);
	for (i = 6; i <10; i++)
		insert_node(&front, i);
	printf(" List elements :\n");
	print_list(front);

	insert_node(&front, 0);
	printf(" List elements after insertion of 0:\n");
	print_list(front);
	insert_node(&front, 5);
	printf(" List elements after insertion of 5:\n");
	print_list(front);

	insert_node(&front, 7);
	printf(" List elements after insertion of 7:\n");
	print_list(front);
	insert_node(&front, 10);
	printf(" List elements after insertion of 10:\n");
	print_list(front);

	delete_node(&front, 0);
	printf(" List elements after deletion of 0:\n");
	print_list(front);
	delete_node(&front, 1);
	printf(" List elements after deletion of 1:\n");
	print_list(front);
	delete_node(&front, 1);
	printf(" List elements after deletion of 1:\n");
	print_list(front);
	delete_node(&front, 5);
	printf(" List elements after deletion of 5:\n");
	print_list(front);
	delete_node(&front, 10);
	printf(" List elements after deletion of 10: \n");
	print_list(front);

	remove_list(&front);
	return 0;
}

 

Comments

Dzięki :)