数据结构----单链表

 

文章目录

• • • 单链表
    • • • 单链表的定义
        • 定义单链表的结构体
        • 初始化函数
        • 添加数据
        • 删除数据
        • 清空内存
        • 完整代码（简单版）

 

单链表

单链表的定义

链式存储的线性表

定义单链表的结构体

typedef struct student
{
	int m_id;
	char m_name[20];
	int m_score;
	struct student *pNext;
}STU;

初始化函数

STU* Init()
{
	STU* pNew = (STU*)malloc(sizeof(STU));
	pNew->pNext = NULL;
	return pNew;
}

添加数据

void Insert(STU* pHead, STU * pData)
{
	STU* pNew = Init();
	pNew->m_id = pData->m_id;
	memcpy(pNew->m_name, pData->m_name, 20);	//字符串不能直接赋值
	pNew->m_score = pData->m_score;
	//中间插入要遍历链表找到插入位置，这里只介绍头插和尾插
#if 0
	//头插
	pNew->pNext = pHead->pNext;	//①
	pHead->pNext = pNew;		//②
#else
	//尾插
	STU* pTemp = pHead;
	while (pTemp->pNext != NULL)
	{
		pTemp = pTemp->pNext;
	}
	pNew->pNext = pTemp->pNext;	//①
	pTemp->pNext = pNew;		//②
#endif
}

删除数据

void DeleteNode(STU* pHead, char name[])
{
	STU* pTemp = pHead;
	while (pTemp->pNext != NULL)
	{
		if (strcmp(pTemp->pNext->m_name, name) == 0)
		{
			STU* pDelete = pTemp->pNext;
			pTemp->pNext = pDelete->pNext;
			free(pDelete);
			break;
		}
		pTemp = pTemp->pNext;
	}
	printf("\n删除成功...\n\n");
}

清空内存

void FreeAll(STU * pHead)
{
	STU* pTemp = pHead;
	while (pTemp->pNext != NULL)
	{
		STU* pDelete = pTemp->pNext;
		pTemp->pNext = pDelete->pNext;
		free(pDelete);
	}
}

完整代码（简单版）

main文件：

//main.c
#include<stdio.h>
#include"linked.h"
int main()
{
	STU* pHead = Init();
	char name[20];
	while (1)
	{
		switch (Menu())
		{
		case 1:		//添加学生信息
		{
			STU* pNew = Init();
			printf("请输入学生ID：");
			scanf("%d", &pNew->m_id);
			printf("请输入学生Name：");
			scanf("%s", pNew->m_name);
			printf("请输入学生Score：");
			scanf("%d", &pNew->m_score);
			Insert(pHead, pNew);
		}
			break;
		case 2:		//删除学生信息
			printf("请输入要删除的学生姓名：");
			scanf("%s", name);
			DeleteNode(pHead, name);
			break;
		case 3:		//修改学生信息
			printf("请输入要修改的学生姓名：");
			scanf("%s", name);
			ChangeNode(pHead, name);
			break;
		case 4:		//查找学生信息
			printf("请输入要查询的学生姓名：");
			scanf("%s", name);
			FindNode(pHead, name);
			break;
		case 5:		//显示学生信息
			PrintList(pHead);
			break;
		case 6:		//退出并删除
			FreeAll(pHead);
			return 0;
			break;
		default:
			break;
		}
	}
	return 0;
}

linked.h文件：

#pragma once
#include<stdlib.h>
#include<stdio.h>
#include<string.h>
#include<conio.h>

typedef struct student
{
	int m_id;
	char m_name[20];
	int m_score;
	struct student *pNext;
}STU;

STU* Init();

void Insert(STU* pHead, STU* pData);
void PrintList(STU* pHead);
void DeleteNode(STU* pHead, char name[]);
void ChangeNode(STU* pHead, char name[]);
void FindNode(STU* pHead, char name[]);
void FreeAll(STU* pHead);
int Menu();

linked.c文件：

//linked.c
#include "linked.h"

STU* Init()
{
	STU* pNew = (STU*)malloc(sizeof(STU));
	pNew->pNext = NULL;
	return pNew;
}

void Insert(STU* pHead, STU * pData)
{
	STU* pNew = Init();
	pNew->m_id = pData->m_id;
	memcpy(pNew->m_name, pData->m_name, 20);	//字符串不能直接赋值
	pNew->m_score = pData->m_score;

#if 0
	//头插
	pNew->pNext = pHead->pNext;
	pHead->pNext = pNew;
#else
	//尾插
	STU* pTemp = pHead;
	while (pTemp->pNext != NULL)
	{
		pTemp = pTemp->pNext;
	}
	pNew->pNext = pTemp->pNext;
	pTemp->pNext = pNew;
#endif
}

void PrintList(STU* pHead)
{
	STU* pTemp = pHead->pNext;	//头结点不储存数据
	printf("-------------------------\n");
	printf("ID\tName\tScore\n");
	while (pTemp != NULL)
	{
		printf("%d\t%s\t%d\n", pTemp->m_id, pTemp->m_name, pTemp->m_score);
		pTemp = pTemp->pNext;
	}
	printf("-------------------------\n");
}

void DeleteNode(STU* pHead, char name[])
{
	STU* pTemp = pHead;
	while (pTemp->pNext != NULL)
	{
		if (strcmp(pTemp->pNext->m_name, name) == 0)
		{
			STU* pDelete = pTemp->pNext;
			pTemp->pNext = pDelete->pNext;
			free(pDelete);
			break;
		}
		pTemp = pTemp->pNext;
	}
	printf("\n删除成功...\n\n");
}

void ChangeNode(STU* pHead, char name[])
{
	STU* pTemp = pHead->pNext;
	while (pTemp != NULL)
	{
		if (strcmp(pTemp->m_name, name) == 0)
		{
			printf("-------------------------\n\n");
			printf("请输入修改后的学生ID：");
			scanf("%d", &pTemp->m_id);
			printf("请输入修改后的学生Name：");
			scanf("%s", pTemp->m_name);
			printf("请输入修改后的学生Score：");
			scanf("%d", &pTemp->m_score);
			printf("\n-------------------------\n");
		}
		pTemp = pTemp->pNext;
	}
	printf("\n修改成功...\n\n");
}

void FindNode(STU* pHead, char name[])
{
	STU* pTemp = pHead->pNext;
	printf("-------------------------\n");
	printf("\n查询学生信息表：\n");
	printf("ID\tName\tScore\n");
	while (pTemp != NULL)
	{
		if (strcmp(pTemp->m_name, name) == 0)
		{
			printf("%d\t%s\t%d\n\n", pTemp->m_id, pTemp->m_name, pTemp->m_score);
			printf("-------------------------\n");
			return;
		}
		pTemp = pTemp->pNext;
	}
}

void FreeAll(STU * pHead)
{
	STU* pTemp = pHead;
	while (pTemp->pNext != NULL)
	{
		STU* pDelete = pTemp->pNext;
		pTemp->pNext = pDelete->pNext;
		free(pDelete);
	}
}

int Menu()
{
	char operate;
	do
	{
		printf("菜单：\n");
		printf("1、添加学生信息：\n");
		printf("2、删除学生信息：\n");
		printf("3、修改学生信息：\n");
		printf("4、查找学生信息：\n");
		printf("5、显示学生信息：\n");
		printf("6、退出并删除：\n");
		operate = getch();
	} while (operate > '5' || operate < '1');
	return operate - '0';
}