学生管理系统

#include<stdio.h>
#include<string.h>
#include<stdlib.h>

void mainMenu();
void admin();
void adminMenu();
void student();
void studentMenu();
void viewStudents();
void viewMarks();
void registerStudent();
void exit();
int  isEqual(char a[],char b[]);

struct Student{
   int rollno;
   char name[20];
   char address[30];
   char username[10];
   char password[10];
   float EnglishMarks;
   float MathsMarks;
   float ScienceMarks;
   float total;
   float average;
   char grade;
}studlist[10];
int x=-1;      // student index is find,-1 means not find
int index=0;   // register numbers of students
//主方法
void main(){
    int choice;
    char username[10]="admin";            //admin username
    char password[10]="admin";            //admin password
    while(1)
    {
    mainMenu();
    scanf("%d",&choice);
    getchar();     //防止输入字符陷入死循环
    switch(choice)
    {
     case 1:
         char AName[10], AWord[10];
         printf("Enter Username:");
         scanf("%s",&AName);
         printf("Enter Password:");
         scanf("%s",&AWord);

        if(isEqual(AName,username) && isEqual(AWord,password))
           admin();
        else
         {
           printf("The username or password  is not right\n");
           main();
         }
         break;


     case 2:
         int i;
         char uName[10], pWord[10];
         printf("Enter Username:");
         scanf("%s",&uName);
         printf("Enter Password:");
         scanf("%s",&pWord);

        // printf("index=%d\n",index);

         for(i=0;i<index;i++)
         {  // printf("isEqualU()=%d,isEqualP()=%d ,%d\n ",isEqual(uName,studlist[i].username) ,isEqual(pWord,studlist[i].password),isEqual(uName,studlist[i].username) && isEqual(pWord,studlist[i].password));

                if(isEqual(uName,studlist[i].username) && isEqual(pWord,studlist[i].password))
                {
                    x=i; //将下标i赋值给全局变量x;
                    student();
                    
                }                
         }
         if(x==-1)
         {
         printf("The username or password  is not right\n");
         }
        break;
     default:printf("You enter the wrong choice!\n");

    }
    }
}

//主菜单
void mainMenu()
{  
  
   printf("---------------------------------------------\n");
   printf("------  Welcome to use StumentSystems! ------\n");
   printf("------      1.Login as Administrator   ------\n");
   printf("------      2.Login as Student         ------\n");
   printf("---------------------------------------------\n");
   printf("Enter Your Choice:");
   
     
}

//管理员菜单
void adminMenu(){
 int choice=-1;
  printf("---------------------------------------------\n");
  printf("------       1. Register Student       ------\n");
  printf("------       2.View Students           ------\n");
  printf("------       3. Exit                   ------\n");
  printf("---------------------------------------------\n");
  printf("Enter Your Choice:");
 
 
}


//学生菜单
void studentMenu()
{
  printf("---------------------------------------------\n");
  printf("------       1. View Marks             ------\n");
  printf("------       2. Exit                   ------\n");
  printf("---------------------------------------------\n");
  printf("Enter Your Choice:");
 
}
//管理员
void admin(){
    int choice=-1;
    while(choice!=3)
    {
    adminMenu();
    scanf("%d",&choice);
    switch(choice)
    {
      case 1:registerStudent();break;
      case 2:viewStudents();break;
      case 3:exit();break;
      default:printf("You enter the wrong choice!\n");
    }
    }
}
//学生
void student(){
    int choice=-1;
    while(choice!=2)
    {
    studentMenu();
    scanf("%d",&choice);
    switch(choice)
    {
      case 1:viewMarks();break;
      case 2:exit();break;
      default:printf("You enter the wrong choice!\n");
    }
    }
}

//登记学生信息
void registerStudent()
{
 
 printf("Enter Details of Student\n");
 printf("Rollno:");
 scanf("%d",&studlist[index].rollno);
 printf("Name:");
 scanf("%s",studlist[index].name);
 printf("Address:");
 scanf("%s",studlist[index].address );
 printf("Username:");
 scanf("%s",studlist[index].username);
 printf("Password:");
 scanf("%s",studlist[index].password);
 printf("English Marks:");
 scanf("%f",&studlist[index].EnglishMarks);
 printf("Maths Marks:");
 scanf("%f",&studlist[index].MathsMarks);
 printf("Science Marks:");
 scanf("%f",&studlist[index].ScienceMarks);
  //总分 平均分 和 等级
 studlist[index].total=studlist[index].EnglishMarks+studlist[index].MathsMarks+studlist[index].ScienceMarks;
 studlist[index].average=(studlist[index].EnglishMarks+studlist[index].MathsMarks+studlist[index].ScienceMarks)/3;
 if(studlist[index].average>=90)
 {
   studlist[index].grade=‘A‘;
 }
 else if(studlist[index].average<90&&(studlist[index].average>=75))
 {
    studlist[index].grade=‘B‘;
 }
 else if(studlist[index].average<75&&(studlist[index].average>=50))
 {
    studlist[index].grade=‘C‘;
 }
 else
 {
    studlist[index].grade=‘F‘;
 }
 printf("Student Registered Successfully !!!\n");

 index++;
 }

//查看学生信息
 void viewStudents()
 {
    int i=0;
   
    printf("Rollno   name   Address  username   password  \n");
     for(i=0;i<index;i++)
          printf("%d       %s      %s      %s         %s  \n",studlist[i].rollno,studlist[i].name,studlist[i].address,
          studlist[i].username,studlist[i].password);
}

//查看学生分数
 void viewMarks()
 {
    printf("English   MAths   Science  Total    AVERAGE   Grade    \n");
    printf("%.2f      %.2f     %.2f     %.2f     %.2f     %c \n",studlist[x].EnglishMarks,studlist[x].MathsMarks,
    studlist[x].ScienceMarks,studlist[x].total,studlist[x].average,studlist[x].grade);
}
 
//退出
 void exit()
 {
  system("cls");
  void main();
 }

//字符串是否相等
 int  isEqual(char a[],char b[])
 {
   int i,j,lenA,lenB;
   lenA=strlen(a);
   lenB=strlen(b);
       if(lenA==lenB)
       {
        for(i=0;i<lenA;i++)
        {
            if(a[i]!=b[i])
            {
                return 0;      
            }       
        }
        return 1;
       }

    return 0;
 }