text: #ifndef _COURSE_MANAGER_H_
  #define _COURSE_MANAGER_H_
  
  typedef struct Courses {
  	/*
  		reg_start[256]: The start date of the course registration
  		reg_end[256]: The end date of the course registration
  		crs_id[256]: The course ID (ex: CSC10002)
  		crs_name[256]: The course name
  		tcher1[256], tcher2[256], tcher3[256], tcher4[256]: The teachers name
  		num_tch: Number of the teachers in the course
  		dSesstion1, dSesstion2: The date that the session will take place (Monday, Tuesday,... Saturday) of the session 1 and the session 2
  		tSesstion1, tSesstion2: The time that the session will take place (7:30, 9:30, 13:30, 15:30) of the session 1 and the session 2
  		max_std: maxium number of students in the course
  	*/
  	
  	char reg_start[256], reg_end[256], crs_id[256], crs_name[256], tcher1[256], tcher2[256], tcher3[256], tcher4[256];
  	long num_tch, credit, dSession1, dSession2, tSesstion1, tSesstion2, max_std = 50;
  }CRses;
  
  typedef struct linkedList {
  	CRses obt;
  	struct linkedList *next, *prev;
  } sCourses;
  
  void addTaleNode_CRS(CRses obt, sCourses *&head, sCourses *&tale);
  
  void addHeadNode_CRS(CRses obt, sCourses *&head, sCourses *&tale);
  
  void deleteNode_CRS(long k, sCourses *&head, sCourses *&tale);
  
  long getListLength_CRS(sCourses *head);
  
  void insertAfterK_CRS(long k, CRses obt, sCourses *&head, sCourses *&tale);
  
  void deallocatingList_CRS(sCourses *& head, sCourses *&tale);
  
  //Delete a course
  void deleteCourse();
  
  //Get new course information from user input. Return true if the new course id doesn't exist in the system, otherwise, return false
  bool getCourseInformation(CRses &courses);
  
  //Update the course information
  void updateCourseInformation();
  
  //print the courses to the screen
  void printCourses();
  
  //get list of the courses, return true if the file 'couses_manager.dat' existed, otherwise, return false
  bool getCoursesLinkedList(sCourses *&head, sCourses *&tale);
  
  //create a course
  void createCourses();
  
  //Get the teacher name when creating the course
  void getTcherName(CRses &courses);
  
  //Return true if the course existed in 'course_manager.dat', otherwise, return false
  bool isCsrIdExisted(CRses courses);
  
  #endif