单向无头链表的基本操作

      对于单向无头链表的基本操作有创建一个链表，销毁，从尾部加一个数进去，从头加一个数进去，从尾部删去一个，从头部删去一个，以及放回这个链表的长度。具体的实现并不难，只是一个简单的逻辑，需要注意的点就是，在进行尾部插入和删除的时候，一定要记得对最后的一个节点的next置为NULL，这样才能保证print函数和Size函数正常进行。

#include <stdio.h>
#include <stdlib.h>

typedef struct List
{
	int date;
	struct List* next;

}List;
void InitList(List *ls)
{
	int i = 0;
	for (i = 0; i < 10; i++)
	{
		ls->date = i;
		ls->next = (List *)malloc(sizeof(List));
		ls = ls->next;
	}
	ls->date = i;
	ls->next = NULL;

}
List *PushFront(List *ls,int date)
{
	List * tmp = (List *)malloc(sizeof(List));
	tmp->date = date;
	tmp->next = ls;
	return tmp;
}
List *PopFront(List *ls)
{
	List *tmp = ls;
	ls = ls->next;
	free(tmp);
	return ls;
}
void PushBack(List *ls, int date)
{
	while (ls->next)
	{
		ls = ls->next;
	}
	ls->next = (List *)malloc(sizeof(List));
	ls->next->date = date;
	ls->next->next = NULL;
	
}
void PopBack(List *ls)
{
	while (ls->next->next)
	{
		ls = ls->next;
	}
	free(ls->next);
	ls->next = NULL;

}
void PrintList(List *ls)
{
	while (ls->next)
	{
		printf("%d ", ls->date);
		ls = ls->next;
	}
	printf("%d ", ls->date);
	printf("\n");
}
void FreeList(List *ls)
{
	if (ls)
	{
		List *tmp;
		while (ls->next)
		{
			tmp = ls->next;
			free(ls);
			ls = tmp;
		}
		free(ls);
		ls = NULL;
	}
}
int Size(List *ls)
{
	int num = 1;
	while (ls->next)
	{
		num++;
		ls = ls->next;
	}
	return num;
}
void main()
{
	List *ls = (List *)malloc(sizeof(List));
	int date = 23;
	InitList(ls);

	ls = PushFront(ls,date);
	ls =PopFront(ls);
	PushBack(ls,date);
	PopBack(ls);
	PrintList(ls);
	printf("%d\n", Size(ls));
	FreeList(ls);


	return 0;
}