Reverse a Linked-list. Write code in C.

There are multiple ways to go about this. Let’s first look at a recursive solution.

Recursive Method:

Node * reverse( Node * ptr , Node * previous)

{

    Node * temp;

    if(ptr->next == NULL) {

        ptr->next = previous;

        return ptr;

    } else {

        temp = reverse(ptr->next, ptr);

        ptr->next = previous;

        return temp;

    }

}

reversedHead = reverse(head, NULL);

Non-Recursive Method

Node * reverse( Node * ptr )

{

    Node * temp;

    Node * previous = NULL;

    while(ptr != NULL) {

        temp = ptr->next;

        ptr->next = previous;

        previous = ptr;

        ptr = temp;

    }

    return previous;

}