Assignment-5_python

The academic office at the Hogwarts School of Witchcraft and Wizardry has compiled data about students' grades. 
The data is provided as text from standard input in three parts: information about courses, information about students and information about grades. 
Each part has a specific line format, described below..

1) Information about courses
   Line format: Course Code~Course Name~Semester~Year~Instructor
2) Information about students
   Line format: Roll Number~Full Name
3) Information about grades
   Line format: Course Code~Semester~Year~Roll Number~Grade
The possible grades are A, AB, B, BC, C, CD, D with corresponding grade points 10, 9, 8, 7, 6, 5 and 4. 
The grade point average of a student is the sum of his/her grade points divided by the number of courses. 
For instance, if a student has taken two courses with grades A and C, the grade point average is 8.50 = (10+7)÷2. 
If a student has not completed any courses, the grade point average is defined to be 0.

You may assume that the data is internally consistent. For every grade, there is a corresponding course code and roll number in the input data.

Each section of the input starts with a line containing a single keyword. The first section begins with a line containing Courses. 
The second section begins with a line containing Students. The third section begins with a line containing Grades. 
The end of the input is marked by a line containing EndOfInput.

Write a Python program to read the data as described above and print out a line listing the grade point average for each student in the following format:

                                              Roll Number~Full Name~Grade Point Average

Your output should be sorted by Roll Number. The grade point average should be rounded off to 2 digits after the decimal point. Use the built-in function round().

Here is a sample input and its corresponding output.

Sample Input:-

Courses
TRAN~Transfiguration~1~2011-2012~Minerva McGonagall
CHAR~Charms~1~2011-2012~Filius Flitwick
Students
SLY2301~Hannah Abbott
SLY2302~Euan Abercrombie
SLY2303~Stewart Ackerley
SLY2304~Bertram Aubrey
SLY2305~Avery
SLY2306~Malcolm Baddock
SLY2307~Marcus Belby
SLY2308~Katie Bell
SLY2309~Sirius Orion Black
Grades
TRAN~1~2011-2012~SLY2301~AB
TRAN~1~2011-2012~SLY2302~B
TRAN~1~2011-2012~SLY2303~B
TRAN~1~2011-2012~SLY2305~A
TRAN~1~2011-2012~SLY2306~BC
TRAN~1~2011-2012~SLY2308~A
TRAN~1~2011-2012~SLY2309~AB
CHAR~1~2011-2012~SLY2301~A
CHAR~1~2011-2012~SLY2302~BC
CHAR~1~2011-2012~SLY2303~B
CHAR~1~2011-2012~SLY2305~BC
CHAR~1~2011-2012~SLY2306~C
CHAR~1~2011-2012~SLY2307~B
CHAR~1~2011-2012~SLY2308~AB
EndOfInput
Sample Input

SLY2301~Hannah Abbott~9.5
SLY2302~Euan Abercrombie~7.5
SLY2303~Stewart Ackerley~8.0
SLY2304~Bertram Aubrey~0
SLY2305~Avery~8.5
SLY2306~Malcolm Baddock~6.5
SLY2307~Marcus Belby~8.0
SLY2308~Katie Bell~9.5
SLY2309~Sirius Orion Black~9.0

Program:
def Gvalue(code):
        if code=="A":
                return(10)
        if code=="AB":
                return(9)
        if code=="B":
                return(8)
        if code=="BC":
                return(7)
        if code=="C":
                return(6)
        if code=="CD":
                return(5)
        if code=="D":
                return(4)
            
ROLL_GRADEsum={}
Roll_course_count={}
Roll_name={}
#courses section

type_course=input()
enter_course_detail=input()
next_input=input()
while(next_input!="Students"):
        next_input=input()

#student section
        
#if it fails in courses section then 
#it will enter students
        
roll,name=input().split('~')
Roll_name[roll]=name
ROLL_GRADEsum[roll]=0
Roll_course_count[roll]=0
next_input=input()
while('~' in next_input):
    roll,name=next_input.split('~')
    Roll_name[roll]=name
    ROLL_GRADEsum[roll]=0
    Roll_course_count[roll]=0
    next_input=input()

#GRADES SECTION

code,sem,year,Rnum,grade=input().split('~')
if Rnum in ROLL_GRADEsum.keys():
    ROLL_GRADEsum[Rnum]=ROLL_GRADEsum[Rnum]+Gvalue(grade)
    Roll_course_count[Rnum]=Roll_course_count[Rnum]+1
next_input=input()
while(next_input!="EndOfInput"):
    code,sem,year,Rnum,grade=next_input.split('~')
    if Rnum in ROLL_GRADEsum.keys():
        ROLL_GRADEsum[Rnum]=ROLL_GRADEsum[Rnum]+Gvalue(grade)
        Roll_course_count[Rnum]=Roll_course_count[Rnum]+1
    next_input=input()
#print(Roll_course_count)
#print(ROLL_GRADEsum)
#print(Roll_name)

Sort_roll=sorted(Roll_name)
for key in Sort_roll:
    if ROLL_GRADEsum[key]!=0:
        ans=round((ROLL_GRADEsum[key]/Roll_course_count[key]),2)
        print(key+"~"+Roll_name[key]+"~"+str(ans))
    else:
        print(key+"~"+Roll_name[key]+"~"+"0")