C言語でリンクリストを理解する方法

--->NULL
head

 ---->[p1]---->[p2]...---->[pn]---->[NULL]
head   p1->next  p2->next   pn->next

typedef struct student{
int score;
struct student *next;
} LinkList;

LinkList *creat(int n){
LinkList *head, *node, *end;//定义头节点，普通节点，尾部节点；
head = (LinkList*)malloc(sizeof(LinkList));//分配地址
end = head;         //若是空链表则头尾节点一样
for (int i = 0; i < n; i++) {
node = (LinkList*)malloc(sizeof(LinkList));
scanf("%d", &node->score);
end->next = node;
end = node;
}
end->next = NULL;//结束创建
return head;
}

void change(LinkList *list,int n) {//n为第n个节点
LinkList *t = list;
int i = 0;
while (i < n && t != NULL) {
t = t->next;
i++;
}
if (t != NULL) {
puts("输入要修改的值");
scanf("%d", &t->score);
}
else {
puts("节点不存在");
}
}

void delet(LinkList *list, int n) {
	LinkList *t = list, *in;
	int i = 0;
	while (i < n && t != NULL) {
		in = t;
		t = t->next;
		i++;
	}
	if (t != NULL) {
		in->next = t->next;
		free(t);
	}
	else {
		puts("节点不存在");
	}
}

void insert(LinkList *list, int n) {
	LinkList *t = list, *in;
	int i = 0;
	while (i < n && t != NULL) {
		t = t->next;
		i++;
	}
	if (t != NULL) {
		in = (LinkList*)malloc(sizeof(LinkList));
		puts("输入要插入的值");
		scanf("%d", &in->score);
		in->next = t->next;//填充in节点的指针域，也就是说把in的指针域指向t的下一个节点
		t->next = in;//填充t节点的指针域，把t的指针域重新指向in
	}
	else {
		puts("节点不存在");
	}
}

        while (h->next != NULL) {
		h = h->next;
		printf("%d  ", h->score);
	}