#include<stdio.h>
#include<stdlib.h>
#include<string.h>
typedef struct subject_info
{
	int number;
	char name[20];
	int score;
	int time;
	int classtime;
	int exprimenttime;
	char term[10];
} subject;
typedef struct student_info
{
	char xh[4];
	char name[10];	
	int subject_num1;
	int subject_num2;
} student;
subject sub;
student stu; 

void infoinput()       //课程信息录入函数 
{
	FILE *fp;
	fp=fopen("si.txt","a+");
	 if(fp==NULL)
        {
	        printf("文件打开失败!\n");
	        exit(0);
        }
    printf("请输入课程编号；\n");
    scanf("%d",&sub.number);
    printf("请输入课程名称；\n");
    scanf("%s",sub.name);
    printf("请输入课程学分；\n");
    scanf("%d",&sub.score);
    printf("请输入课程学时；\n");
    scanf("%d",&sub.time);
    printf("请输入授课学时；\n");
    scanf("%d",&sub.classtime);
    printf("请输入实验学时；\n");
    scanf("%d",&sub.exprimenttime);
    printf("请输入开课学期；\n");
    scanf("%s",sub.term);
    fprintf(fp,"\n%d\t%s\t%d\t%d\t%d\t%d\t%s\t\n",sub.number,sub.name,sub.score,sub.time,sub.classtime,sub.exprimenttime,sub.term);
    if(fclose(fp))
	 {
		printf("无法关闭文件！\n");
	  	exit(0);
	 }
}

void studentinfo()   //学生选课信息录入 
{
	FILE *fp;
	fp=fopen("student.txt","a+");
	if(fp==NULL)
	{
		printf("文件打开失败!");
		exit(0);
	}
	printf("请输入学生学号：");
	scanf("%s",stu.xh);
	printf("请输入学生姓名：");
	scanf("%s",stu.name);
	printf("请输入您选的第一门课程的编号：");
	scanf("%d",&stu.subject_num1);
	printf("请输入您选的第二门课程的编号：");
	scanf("%d",&stu.subject_num2); 
	fprintf(fp,"\n%s\t%s\t%d\t%d\t\n",stu.xh,stu.name,stu.subject_num1,stu.subject_num2);
	if(fclose(fp))
	 {
		printf("无法关闭文件！");
	  	exit(0);
	 }
}

void lookthrough()  //课程信息浏览 
{
	FILE *fp;
	fp=fopen("si.txt","r");
		if(fp==NULL)
	{
		printf("文件打开失败!");
		exit(0);
	}
	rewind(fp);
	printf("选修课程信息一览表\n");
	printf("编号\t名称\t学分\t学时\t授课学时\t实验学时\t开课学期\n");
	while(!feof(fp))
	{
		fscanf(fp,"%d\t%s\t%d\t%d\t%d\t%d\t%s\t",&sub.number,sub.name,&sub.score,&sub.time,&sub.classtime,&sub.exprimenttime,sub.term);
		printf("\n%d\t%s\t%d\t%d\t%d\t         %d\t        %s\t\n",sub.number,sub.name,sub.score,sub.time,sub.classtime,sub.exprimenttime,sub.term);
	 } 
		if(fclose(fp))
	  {
	  	printf("无法关闭文件！\n");
	  	exit(0);
	  }	  
}

void xh_cx()   //按学号查询
{char s[4];
char a[4]="";
FILE *fp;
int flag=0;
 printf("请输入查询的学号:");
 scanf("%s",s);
fp=fopen("student.txt","r");  
 if(fp==NULL)
   {
        printf("文件打开失败!");
        exit(1);
   }
    rewind(fp);
   while(!feof(fp))
    {
        fscanf(fp,"%s%s%d%d",stu.xh,stu.name,&stu.subject_num1,&stu.subject_num2);
      strncpy(a,stu.xh,4);
  
  if(strcmp(a,s)==0)
{
printf("%s\t%s\t%d\t%d\n",stu.xh,stu.name,stu.subject_num1,stu.subject_num2);
flag=1;
}
}
  if(flag==0)
printf("Not Found!\n");       
   if(fclose(fp))
	 {
		printf("无法关闭文件！");
	  	exit(0);
	 }
}

void score_cx()     //按学分查询
{
	FILE *fp;
	int xf,a;int flag=0; 
	fp=fopen("si.txt","r");
	if(fp==NULL)
	{
		printf("文件打开失败!");
		exit(1);
	}
	rewind(fp);
	printf("请输入学分：");
	scanf("%d",&xf);
	while(!feof(fp))
	{		
		    fscanf(fp,"%d\t%s\t%d\t%d\t%d\t%d\t%s\t",&sub.number,sub.name,&sub.score,&sub.time,&sub.classtime,&sub.exprimenttime,sub.term);
		    a=sub.score;
		    if(xf==a)
		        {
		            printf("%d\t%s\t%d\t%d\t%d\t%d\t%s\t\n",sub.number,sub.name,sub.score,sub.time,sub.classtime,sub.exprimenttime,sub.term);
			        flag=1;
				}
	}
	if(flag==0)
	printf("Not Found!\n");
	if(fclose(fp))
	 {
		printf("无法关闭文件！");
	  	exit(0);
	 }
}


int main()
{
	int n;
	do
	{
	printf("\n学生选课系统\n\n");
	printf("------------------\n");
	printf("| 1.课程信息录入 |\n");
	printf("| 2.选课信息录入 |\n"); 
	printf("| 3.课程信息浏览 |\n");
	printf("| 4.按学号查询   |\n");
	printf("| 5.按学分查询   |\n");
	printf("| 6.退出         |\n"); 
	printf("------------------\n\n");
	printf("请输入服务选项：");
	scanf("%d",&n);
	switch(n)
	{
		case 1:
		        {
		        	system("cls");
		        	infoinput();
				    break;
			    }
		case 2: 
		       {
			        system("cls");
			        studentinfo();
					break;
	        	}  
		case 3: 
		        {
		        	system("cls");
		        	lookthrough();
		        	break;
				  }  
		case 4: 
		        {
		        	system("cls");
		        	xh_cx();
		        	break;
				  }  
		case 5:  
		        {
		        	system("cls");
		        	score_cx();
		        	break;
				}
		case 6:  
		       {
		       	   system("cls");
		       	   printf("欢迎使用本系统。谢谢！"); 
			   }
		default:break;
	}
	} while(n!=6);
}