第16题 reverse every K elements of a linked list

Write a program to reverse every K elements of a linked list.

Example: K = 3

1->2->3->4->5->6->NULL

output: 3->2->1->6->5->4-NULL

struct node *reverse (struct node *head, int k)
{
    struct node* current = head;
    struct node* next;
    struct node* result = NULL;
    int count = 0; 
    while (current != NULL && count < k)
    {
         next = current->next;
         current->next = result;
         result = current;
         current = next;
         count++;
    }
    if(next != NULL)
    { 
        head->next = reverse(next, k);
    }
    return result;
}