Here are some annotations (and minor edits to reduce the amount of code).
/* Linked list node definition */
struct node {
int val;
struct node * next;
};
int main() {
int i;
struct node *head, *new_node;
head = NULL;
for (i = 1; i <= 10; i++) {
// Allocate a new node and initialize its components (val and next)
new_node = (struct node *) malloc(sizeof(node));
new_node->val = i;
new_node->next = NULL;
// The if block is actually not necessary...
if (head == NULL) {
// If the linked list is empty, set the head pointer to the initial node
head = new_node;
} else {
// Now that you have your new node, connect it. Start:
// head->[current linked list]
// [new_node.next]->NULL
new_node->next = head;
// head->[current linked list]->...
// [new_node.next]->[current linked list]->...
head = newnode;
// head->[new_node.next]->[current linked list]->...
}
}
}
The key thing is that malloc
returns a pointer to memory. Each new node is allocated dynamically and thus is a location in memory (not a basic type).