C语言实现简单的循环链表

#include<stdio.h>
#include <malloc.h>
typedef struct LinkNode {
	struct LinkNode* next;
}LinkNode;
typedef struct circlelist {
	int size;
	LinkNode head;
}CircleList;
CircleList* Init_list() {
	CircleList* circlelist = (CircleList*)malloc(sizeof(CircleList));
	circlelist->size = 0;
	circlelist->head.next = NULL;
}
LinkNode* lastp(CircleList*circlelist) {//得到尾结点
	LinkNode* tmp = circlelist->head.next;
	while (tmp != &(circlelist->head)) {
		tmp = tmp->next;
	}
	return tmp;
}
LinkNode gettop(CircleList* circlelist) {//得到头结点
	return circlelist->head;
}
void insert_list(CircleList* circlelist,LinkNode *data) {//尾插法
	LinkNode* last = lastp(circlelist);
	last->next = data;
	data->next = &(circlelist->head);
}
void delete_listnode(CircleList* circlelist) {//删除尾结点
	LinkNode* tmp = &(circlelist->head);

	while (tmp->next != lastp(circlelist)) {
		tmp = tmp->next;
	}
	LinkNode* last = tmp->next;
	tmp->next = &(circlelist->head);
	free(last); // 释放最后一个节点的内存
}

int main() {

	return 0;
}