数据结构----单链表

老师的代码

#include <stdio.h>
#include <malloc.h>

/*
  Linked list of characters. The key is data.
 */
typedef struct LinkNode//结点定义类型
{	
    char data;
	struct LinkNode *next;
} LNode, *LinkList, *NodePtr;//LinkList为结构体指针类型

/*
  Initialize the list with a header.
  @return The pointer to the header.
 */
LinkList initLinkList(){
	NodePtr tempHeader = (NodePtr)malloc(sizeof(LNode));
	tempHeader->data = '\0';
	tempHeader->next = NULL;
	return tempHeader;
}// Of initLinkList

/*
  Print the list.
  @param paraHeader The header of the list.
 */
void printList(NodePtr paraHeader)
{
	NodePtr p = paraHeader->next;
	while (p != NULL) {
		printf("%c", p->data);
		p = p->next;
	}// Of while
	printf("\r\n");
}// Of printList

/*
  Add an element to the tail.
  @param paraHeader The header of the list.
  @param paraChar The given char.
 */
void appendElement(NodePtr paraHeader, char paraChar)
{
	NodePtr p, q;

	// Step 1. Construct a new node.
	q = (NodePtr)malloc(sizeof(LNode));
	q->data = paraChar;
	q->next = NULL;

	// Step 2. Search to the tail.
	p = paraHeader;
	while (p->next != NULL) {
		p = p->next;
	}// Of while

	// Step 3. Now add/link.
	p->next = q;
}// Of appendElement

/*
  Insert an element to the given position.
  @param paraHeader The header of the list.
  @param paraChar The given char.
  @param paraPosition The given position.
 */
void insertElement(NodePtr paraHeader, char paraChar, int paraPosition)
{
	NodePtr p, q;

	// Step 1. Search to the position.
	p = paraHeader;
	for (int i = 0; i < paraPosition; i ++) {
		p = p->next;
		if (p == NULL) {
			printf("The position %d is beyond the scope of the list.", paraPosition);
			return;
		}// Of if
	} // Of for i

	// Step 2. Construct a new node.
	q = (NodePtr)malloc(sizeof(LNode));
	q->data = paraChar;

	// Step 3. Now link.
	printf("linking\r\n");
	q->next = p->next;
	p->next = q;
}// Of insertElement

/*
  Delete an element from the list.
  @param paraHeader The header of the list.
  @param paraChar The given char.
 */
void deleteElement(NodePtr paraHeader, char paraChar)
{
	NodePtr p, q;
	p = paraHeader;
	while ((p->next != NULL) && (p->next->data != paraChar)){
		p = p->next;
	}// Of while

	if (p->next == NULL) {
		printf("Cannot delete %c\r\n", paraChar);
		return;
	}// Of if

	q = p->next;
	p->next = p->next->next;
	free(q);
}// Of deleteElement

/*
  Unit test.
 */
void appendInsertDeleteTest()
{
	// Step 1. Initialize an empty list.
	LinkList tempList = initLinkList();
	printList(tempList);

	// Step 2. Add some characters.
	appendElement(tempList, 'H');
	appendElement(tempList, 'e');
	appendElement(tempList, 'l');
	appendElement(tempList, 'l');
	appendElement(tempList, 'o');
	appendElement(tempList, '!');
	printList(tempList);

	// Step 3. Delete some characters (the first occurrence).
	deleteElement(tempList, 'e');
	deleteElement(tempList, 'a');
	deleteElement(tempList, 'o');
	printList(tempList);

	// Step 4. Insert to a given position.
	insertElement(tempList, 'o', 1);
	printList(tempList);
}// Of appendInsertDeleteTest

/*
  Address test: beyond the book.
 */
void basicAddressTest()
{
	LNode tempNode1, tempNode2;

	tempNode1.data = 4;
	tempNode1.next = NULL;

	tempNode2.data = 6;
	tempNode2.next = NULL;

	printf("The first node: %d, %d, %d\r\n",
		&tempNode1, &tempNode1.data, &tempNode1.next);
	printf("The second node: %d, %d, %d\r\n",
		&tempNode2, &tempNode2.data, &tempNode2.next);

	tempNode1.next = &tempNode2;
}// Of basicAddressTest

/*
  The entrance.
 */
int main(){
	appendInsertDeleteTest();
}// Of main

头插法

 尾插法

 单链表的存储结构

typedef struct Node//结点类型定义
{
	ElemType data;
	struct Node *next;
}Node,*LinkList;//LinkList为结构体指针类型

 初始化单链表

InitList(LinkList *L)
{
	*L=(LinkList)malloc(sizeof(Node));//建立头结点
	(*L)->next=NULL;//建立空的单链表
 
}

 头插法

void CerateFromHead(LinkList L)
//L是带头结点的空链表头指针，通过键盘输入表中元素值，利用头插法建立单链表L
{
    Node*s;
    char c;
    int flag=1;
    while(flag)//flag初值为1，当输入$时置flag为0，建表结束
    {
        c=getchar();
        if(c!='$')
        {
            s=(Node*)malloc(sizeof(Node));//建立新节点
            s->data=c;
            s->next=L->next;//将s插入表头
            L->next=s;
 
        }
        else
            flag=0;
    }
}

尾插法

void CreateFromTail(LinkList L)
{
    Node *r,*s;
    int flag=1;
    r=L;
    while(flag)
    {
        c=getchar();
        if(c!='$')
        {
            s=(Node *)malloc(sizeof(Node));
            s->data=c;
            r->next=s;
            r=s;
 
        }
        else
        {
            flag=0;
            r->next=NULL;//将最后一个结点的next链域置为空，表示链表的结束
        }
    }
    
}

运行结果