数据结构与算法-链表

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/************************************************************雇员链表****************************************************************/
//定义数据结构
typedef struct _employee
{
	char name[32];
	unsigned char age;
}Employee;
//定义节点
typedef struct _node
{
	void *data;
	struct _node *next;
}Node;
//定义链表的维护结构体
typedef struct _linkedlist
{
	Node *head;
	Node *tail;
	Node *current;
}LinkedList;
/****************************使用函数指针支持雇员信息比较及打印****************************/
int compareEmployee(Employee *e1,Employee *e2)
{
	return strcmp(e1->name,e2->name);
}
void displayEmployee(Employee *emp)
{
	printf("%s\t%d\n",emp->name,emp->age);
}
typedef int(*COMPARE)(void*,void*);//compareEmployee函数指针类型定义
typedef void(*DISPLAY)(void*);//displayEmployee函数指针类型定义
/*****************************************************************************************/
//支持链表功能的函数
void initializeList(LinkedList* list);//初始化链表
void addHead(LinkedList* list,void* data);//给链表的头节点添加数据
void addTail(LinkedList* list,void* data);//给链表的尾节点添加数据
void delete(LinkedList* list,Node* node);//从链表删除节点
Node* getNode(LinkedList* list,COMPARE,void* data);//返回包含指定数据的节点指针
void displayLinkedList(LinkedList* list,DISPLAY);//打印链表
//初始化链表
void initializeList(LinkedList* list)
{
	list->head = NULL;
	list->tail = NULL;
	list->current = NULL;
}
//给链表的头节点添加数据
void addHead(LinkedList* list,void* data)
{
	Node* node = (Node*)malloc(sizeof(Node));
	node->data = data;
	if(list->head == NULL)//首次向头节点添加内容
	{
		list->tail = node;
		node->next = NULL;//链表的尾节点不指向任何节点
	}
	else
	{
		node->next = list->head;//新的节点指向原来的头节点
	}
	list->head = node;
}
//给链表的尾节点添加数据
void addTail(LinkedList* list,void* data)
{
	Node* node = (Node*)malloc(sizeof(Node));
	node->data = data;
	node->next = NULL;
	if(list->tail == NULL)
	{
		list->head = node;
	}
	else
	{
		list->tail->next = node;//尾节点指向新节点
	}
	list->tail = node;//尾节点被更新
}

//显示链表节点
void displayLinkedList(LinkedList *list,DISPLAY display)
{
	printf("Linked List\n");
	Node *current = list->head;
	while(current != NULL)
	{
		display(current->data);
		current = current->next;
	}
}

//返回包含指定数据的节点指针
Node* getNode(LinkedList* list,COMPARE compare,void* data)
{
	Node *node;
	node = list->head;
	while(node != NULL)
	{
		if(compare(node->data,data) == 0)
		{
			return node;
		}
		node = node->next;
	}
	return NULL;
}

//删除节点
void delete(LinkedList *list,Node *node)
{
	if(node == list->head)//要删除的节点是链表的头节点
	{
		if(list->head->next == NULL)
		{
			list->head = list->tail =NULL;
		}
		else
		{
			list->head = list->head->next;
		}
	}
	else
	{
		Node *tmp = list->head;
		while(tmp != NULL && tmp->next != node)
		{
			tmp = tmp->next;
		}
		if(tmp != NULL)
		{
			tmp->next = node->next;
		}		
	}
	free(node);
}

void main()
{
	DISPLAY displa = (void*)displayEmployee;
	LinkedList *linkedList = (LinkedList*)malloc(sizeof(LinkedList));
	Employee *samuel = (Employee*)malloc(sizeof(Employee));
	strcpy(samuel->name,"Samuel");
	samuel->age = 32;
	
	Employee *sally = (Employee*)malloc(sizeof(Employee));
	strcpy(sally->name,"Sally");
	sally->age = 28;

	Employee *susan = (Employee*)malloc(sizeof(Employee));
	strcpy(susan->name,"Susan");
	susan->age = 45;
	initializeList(linkedList);//初始化
	addTail(linkedList,samuel);
	addTail(linkedList,sally);
	addTail(linkedList,susan);
	Node *node = getNode(linkedList,(COMPARE)compareEmployee,sally);
	delete(linkedList,node);
	//displayLinkedList(linkedList,(DISPLAY)displayEmployee);
	displayLinkedList(linkedList,displa);
}