Question

Rewrite this to minimize the assignment statements

/*
 Build the list {1, 2, 3} in the heap and store
 its head pointer in a local stack variable.
 Returns the head pointer to the caller.
*/
struct node* BuildOneTwoThree() {
struct node* head = NULL;
struct node* second = NULL;
struct node* third = NULL;
head = malloc(sizeof(struct node)); // allocate 3 nodes in the hea
second = malloc(sizeof(struct node));
third = malloc(sizeof(struct node));
head->data = 1; // setup first node
head->next = second; // note: pointer assignment rule
second->data = 2; // setup second node
second->next = third;
third->data = 3; // setup third link
third->next = NULL;
// At this point, the linked list referenced by "head"
// matches the list in the drawing.
return head;
}

From http://cslibrary.stanford.edu/

Answer 1

node *head;
node **next= &head;

int next_value= 1;
while (next_value<=3)
{
    *next= malloc(sizeof(struct node));
    (*next)->data= next_value;
    next= &(*next)->next;
    ++next_value;
}

*next= 0;