C语言链表实现简单的学生信息管理系统

迈不过友情╰ 2022-02-27 23:36 203阅读 0赞

C语言链表实现增删查改

#include<stdio.h>
    #include<stdlib.h>
    #include<string.h>
    
    typedef struct student{
    	char num[20];
    	char name[20];
    	int Chanese;
    	int English;
    	int Math; 
    	struct student *next;
    }Lnode,* LinkList;
    void Display(LinkList list){
    	Lnode *p = list->next;
    	while( p != NULL ){
    		printf("链表值为：\n");
    		printf("%-16s%-16s%-8d%-8d%-8d\n",p->num,p->name,p->Chanese,p->English,p->Math);
    		p = p->next;
    	}
    }
    void InitList(LinkList list){
    	Lnode *head=list;
    	head = (LinkList)malloc(sizeof(Lnode));
    	head->next = NULL;
    }
    
    void AddStudent(LinkList list){
    	Lnode *p = list,*node;
    	node = (LinkList)malloc(sizeof(Lnode));
    	while(p->next != NULL){
    		p = p->next;
    	}
    	p->next = node;
    	p = node;
    	printf("请输入该生的学号,姓名，语文成绩，英语成绩，数学成绩：\n");
    	scanf("%s",&node->num);
    	scanf("%s",&node->name);
    	scanf("%d",&node->Chanese);
    	scanf("%d",&node->English);
    	scanf("%d",&node->Math);
    	p->next = NULL;
    }
    void Search_name(LinkList list){
    	Lnode *p = list->next;
    	char a[20];
    	printf("请输入要查找学生的姓名：\n");
    	scanf("%c",&a);
    	while( p != NULL ){
    		if(strcmp(a,p->name) == 0){
    			printf("查找结果如下：\n学号\t姓名\t语文成绩\t英语成绩\t数学成绩\t");
    			printf("%-16s%-8s%-8d%-8d%-8d\n",p->num,p->name,p->Chanese,p->English,p->Math); 
    		}
    		p = p->next;
    	}
    }
    void Search_num(LinkList list){
    	Lnode *p = list->next;
    	char a[20];
    	printf("请输入要查找学生的学号：\n");
    	scanf("%s",&a);//不要忘了去地址符 
    	//Display(p);
    	//printf("输入的值为：%s",a); 
    	while( p != NULL ){
    		if(strcmp(a,p->num) == 0){
    			printf("查找结果如下：\n学号\t姓名\t语文成绩\t英语成绩\t数学成绩\t\n");
    			printf("%-s\t%-s%\t%-d\t%-d\t%-d\t\n",p->num,p->name,p->Chanese,p->English,p->Math); 
    		}
    		p = p->next;
    	}
    }
    void SearchStudent(LinkList list){
    	int n = 0;
    	printf("请选择查找方式：\n1.按姓名查找\n2.按学号查找\n");
    	scanf("%d",&n);
    	printf("输入的值为：%d\n",n);
    	if ( n==1 ){
    		Search_name(list);
    	}
    	else if( n==2 ){
    		Search_num(list);
    	}
    	else{
    		printf("输入有误！\n");
    	}	
    }
    void Dele_name(LinkList list){
    	Lnode *pre = list,*p = pre->next,*q;
    	char a[20];
    	printf("请输入要删除学生的姓名：\n");
    	scanf("%s",&a);
    	while( p != NULL ){
    		if(strcmp(a,p->name) == 0){
    			q = p;						//	q = p;
    			p = p->next;				//	pre->next = p->next;
    			pre->next = p;				//	p = p->next;
    			free(q);					//注意上面的错误 
    		}
    		else{//这里要加else 
    			pre = p;
    			p = p->next;	
    		}	
    	}
    }
    void Dele_num(LinkList list){
    	Lnode *pre = list,*p = pre->next,*q;
    	char a[20];
    	printf("请输入要删除学生的学号：\n");
    	scanf("%s",&a);//要用%s 和 &a  
    	while( p != NULL ){
    		printf("测试\n");
    		if(strcmp(a,p->num) == 0){
    		
    			q = p;
    			p = p->next;
    		//	pre->next = p->next; 
    		//	p = pre->next;
    			pre->next = p;
    			free(q);
    			printf("测试2\n");
    		}
    		else{
    			pre = p;
    			p = p->next;	
    		}
    		
    	}
    }
    void DeleStudent(LinkList list){
    	printf("选择删除方式：\n1.按姓名删除\n2.按学号删除\n");
    	int n = 0;
    	scanf("%d",&n);
    	if ( n==1 ){
    		Dele_name(list);
    	}
    	else if( n==2 ){
    		Dele_num(list);
    	}
    	else{
    		printf("输入有误！\n");
    	}	
    }
    void Change_name(LinkList list){
    	Lnode *p = list->next;
    	char a[20],s[20];
    	int n=0;
    	printf("请输入要修改学生的姓名：\n");
    	scanf("%s",&a);
    	while( p != NULL ){
    		if(strcmp(a,p->name) == 0){
    			printf("选择要修改的学生信息；\n"); 
    			printf("1.学号 2.姓名 3.语文成绩 4.英语成绩 5.数学成绩"); 
    			scanf("%d",&n);
    			switch(n){
    			case 1:
    				printf("学号修改为：\n");
    				scanf("%s",&p->num); break;
    			case 2:
    				printf("姓名修改为：\n");
    				scanf("%s",&p->name);break;
    			case 3:
    				printf("语文成绩修改为：\n");
    				scanf("%d",&p->Chanese);break;
    			case 4:
    				printf("英语成绩修改为：\n");
    				scanf("%d",&p->English);break;
    			case 5:
    				printf("数学成绩修改为：\n");
    				scanf("%d",&p->Math);break;		
    			}
    			p = p->next;
    		}
    		else
    			p = p->next;
    	}
    }
    void Change_num(LinkList list){
    	Lnode *p = list->next;
    	char a[20],s[20];
    	int n=0;
    	printf("请输入要修改学生的学号：\n");
    	scanf("%s",&a);
    	while( p != NULL ){
    		if(strcmp(a,p->num) == 0){
    			printf("选择要修改的学生信息；\n"); 
    			printf("1.学号 2.姓名 3.语文成绩 4.英语成绩 5.数学成绩"); 
    			scanf("%d",&n);
    			switch(n){
    			case 1:
    				printf("学号修改为：\n");
    				scanf("%s",&p->num); break;
    			case 2:
    				printf("姓名修改为：\n");
    				scanf("%s",&p->name);break;
    			case 3:
    				printf("语文成绩修改为：\n");
    				scanf("%d",&p->Chanese);break;
    			case 4:
    				printf("英语成绩修改为：\n");
    				scanf("%d",&p->English);break;
    			case 5:
    				printf("数学成绩修改为：\n");
    				scanf("%d",&p->Math);break;
    			}
    			p = p->next;
    		}
    		else
    			p = p->next;
    	}
    }
    void ChangeStudent(LinkList list){
    	printf("选择修改方式：\n1.查姓名修改\n2.查学号修改\n");
    	int n = 0;
    	scanf("%d",&n);
    	if ( n==1 ){
    		Change_name(list);
    	}
    	else if( n==2 ){
    		Change_num(list);
    	}
    	else{
    		printf("输入有误！\n");
    	}
    }
    
    int Average(LinkList list){
    	Lnode *p = list->next;
    	int count = 0, aver = 0, sum = 0;
    	int n;
    	printf("选择哪一门的平均成绩：\n1.语文 2.英语 3.数学 \n");
    	scanf("%d",&n);
    	switch (n){
    		case 1:
    			#define  subject p->Chanese
    			break; 
    		case 2:
    			#define  subject p->English
    			break; 
    		case 3:
    			#define  subject p->Math
    			break; 		
    	}
    	while( p != NULL ){
    		count++;
    		printf("%d次的值为%d\n",count,subject);
    		sum += subject;
    		printf("sum值为：%d\n",sum);
    		p = p->next;
    	}
    	return aver = sum/count;
    }
    
    
    int main(){
    	LinkList list;
    	int aver=0;
    	AddStudent(list);
    //	SearchStudent(list);
    //	AddStudent(list);
    //	DeleStudent(list);
    //	Display(list);
    //	ChangeStudent(list);
    //	Display(list);
    //	AddStudent(list);
    	AddStudent(list);
    	aver = Average(list);
    	printf("平均值为：%d\n",aver);
    }