p6lkxhwn4/2.cpp

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<malloc.h>
int n;//学生总数 
struct student
{
	char id[20];
	char name[20];
	int math,chinese,english,sum;
	float avg;
	struct student *next;
 };
//函数声明
struct student *creat(struct student *head);    //数据输入 
struct student *put(struct student *head);   //数据输出显示 
struct student *delet(struct student *head,char *id);    //数据删除 
struct student *query(struct student *head,char *id);    //数据查询 
struct student *update(struct student *head,char *id);   //数据修改 
struct student *order(struct student *head,int sum);   //成绩排序 

int menu_select()
{
	char a;
	do
	{
	    printf("\t\t ╭══════════════ ╮\n");  
        printf("\t\t |         学生成绩管理系统      │\n");  
        printf("\t\t╰═══════════════╯\n");  
        printf("\t\t   ┌────────────────┐\n");  
        printf("\t\t   │ 1. 信息输入    2. 显示记录     │\n");  
        printf("\t\t   │                                │\n");  
        printf("\t\t   │ 3. 信息查询    4. 成绩排序     │\n"); 
        printf("\t\t   │                                │\n");  
        printf("\t\t   │ 5. 修改信息    6. 删除信息     │\n");  
        printf("\t\t   │                                │\n");  
        printf("\t\t   │ 0. 退出系统                    │\n"); 
        printf("\t\t   └────────────────┘\n");  
        printf("\t\t请您选择(0-6):");  
    a=getchar();
	}while(a>'6'||a<'0');
	return (a-'0');
}

struct student *creat()
{  
   struct student *head;
   struct student *p1,*q1;
   q1=head;
   while(p1)
   {
   p1=(struct student*)malloc(sizeof(struct student));
   p1=p1->next;
   printf("\t现在开始输入学生信息");
   printf("\t请输入学生学号；");
   scanf("%s",&p1->id);
   printf("\t请输入学生姓名；");
   scanf("%s",&p1->name);
   printf("\t请输入学生高等数学成绩"); 
   scanf("%d",&p1->math);
   printf("\t请输入学生大学语文成绩；");
   scanf("%d",&p1->chinese);
   printf("\t请输入学生大学英语成绩；");
   scanf("%d",&p1->english); 
   p1->avg=(p1->math+p1->english+p1->chinese)/3;
   p1->sum=p1->math+p1->english+p1->chinese;
   p1->next=NULL;//尾插法语句 
   q1->next=p1;
   q1=p1;//尾插法结束 
   }
}


struct student *put(struct student *head)
{   
  struct student *p2;
  printf("-------------------------------------------------------------");
  printf("|学号   姓名   高等数学   大学语文  大学英语   平均分   总分 | "); 
  printf("-------------------------------------------------------------");
  p2=head;
  if(p2!=NULL) 
  do
  {
  	printf("-%s",p2->id);
  	printf("-%s",p2->name);
  	printf("-%d",p2->math);
  	printf("-%d",p2->chinese);
  	printf("-%d",p2->english);
  	printf("-%f",p2->avg);
  	printf("-%d",p2->sum);
  	p2->next;
  }while(p2!=NULL);
}

struct student *query(struct student *head,char *id)
{
	struct student *p3,*q2;
	p3=head;
   if(head==NULL)
	{
	printf("链表为空");
	}
	else
	{
		while(p3->id!=id&&p3->next!=NULL)
		{
			q2=p3;
			p3=p3->next;
		}
		if(p3->id==id)
		{
	printf("%s",p3->id);
  	printf("%s",p3->name);
  	printf("%d",p3->math);
  	printf("%d",p3->chinese);
  	printf("%d",p3->english);
  	printf("%f",p3->avg);
  	printf("%d",p3->sum);
	}
	
}

struct student *update(struct student *head,char *id)
{
	struct student *p4,*p7;
	p7=(struct student*)malloc(sizeof(struct student));
	p4=head;
	if(head==NULL)
	{
	printf("链表为空");
	}
	else
	{
		while(p4->id!=id&&p4->next!=NULL)
		{
			p7=p4;
			p4=p4->next;
		}
		if(p4->id==id)
		{
		 p4->chinese=p7->chinese;
		 p4->math=p7->math;
		 p4->english=p7->english;
		 p7->sum=p7->math+p7->english+p7->chinese;
		 p7->avg=(p7->math+p7->english+p7->chinese)/3;	
		}
	} 
	return head;
}
struct student *delet(struct student *head,char *id)
{
	struct student *p5,*p6;
	p5=head;
	if(head==NULL)
	{
	printf("链表为空");
	}
	else
	{
		while(id!=p5->id&&p5->next!=NULL)
	{
		p6=p5;
		p5=p5->next;
	} 
	if(p5->id==id)
	{
	   if(p5==head)
	   head=p5->next;
	   else 
	   {
	   p6->next=p5->next;
	   n=n-1;
	   free(p5);
       }
	}
	else 
	printf("该学号不在系统中，无法操作");
	}
	return head; 
}

struct student *order(struct student *head,int sum)
{
	struct student *p8,*p9;
	int t; 
	p8=head;
	for(p8;p8!=NULL;p8->next) 
	{ 
		for(p9=p8->next; p9!=NULL; p9=p9->next)
		{ 
			if(p8->sum>p9->sum) 
			{ 
			t=p8->sum; 
			p8->sum = p9->sum; 
			p9->sum=t; 
			}
		}
	}
}
 
int main()
{
	int n;
    struct student *head;
    head=(struct student*)malloc(sizeof(struct student));
    head->next=NULL;
	switch(menu_select())
	{
		case 1:
		printf("学生信息输入");
		struct student *creat(struct student *head);
		break;
		case 2:
	    printf("学生信息显示");
		struct student *put(struct student *head);
		break;
		case 3:
		printf("学生信息查找");
		scanf("%s",p->id)
		struct student *query(struct student *head,char *id);
		break;
		case 4:
		printf("学生成绩排序");
		struct student *order(struct student *head,int sum);
		break;
		case 5:
		printf("学生成绩修改");
		struct student *update(struct student *head,char *id);
		struct student *put(struct student *head);
		break;
		case 6:
	    printf("学生成绩删除");
		struct student *delet(struct student *head,char *id);
		struct student *put(struct student *head);
        break;
        case 0:
        printf("\n\t\t谢谢使用，再见!\n");  
        printf("\n\t\t");  
        system("pause");  
        exit(0); 	
	}
	return 0;
}