create a menu and display options like :
1.add student records
2.modify student records
3.display student records
-implement option-1 to add recordds into a file 'student.dat'.
it should ask first to enter student's personal details :like-'student ID','name','address','phone'etc.than store it into file
-implement option should-3 to display content of the file 'student.dat'
-exit option should terminate the application
-a message 'modification is not allowed'should be displayed when option-2 is selected