please give me the perfect c programme

File: 4) typedef struct char name[50); int id; char dept[20); double egpa; student; a) Write a function void saveByDept(char*fileName, char * deptName, student allStudents[], int size) that will save the information of all students who belong to the department with name pointed to by deptName into a text file. The name of the file is given as an input parameter, filename. b) Write another function to delete the students of the department with a CGPA greater than or equal to 3 from the file you have created in part (a)