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Question

The following function reverse() is supposed to reverse a singly linked list. There is one line missing at the end of the function.

/* Link list node */
struct node
{
    int data;
    struct node* next;
};
 
/* head_ref is a double pointer which points to head (or start) pointer
  of linked list */
static void reverse(struct node** head_ref)
{
    struct node* prev   = NULL;
    struct node* current = *head_ref;
    struct node* next;
    while (current != NULL)
    {
        next  = current->next; 
        current->next = prev;  
        prev = current;
        current = next;
    }
    /*ADD A STATEMENT HERE*/
}

What should be added in place of "/*ADD A STATEMENT HERE*/", so that the function correctly reverses a linked list.

a.

*head_ref = prev;

b.

*head_ref = current;

c.

*head_ref = next;

d.

*head_ref = NULL;

Answer: (a).*head_ref = prev;

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Q. The following function reverse() is supposed to reverse a singly linked list. There is one line missing at the end of the function. /* Link list node */ struct node {     int...

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