GPA

2022-09-19.py

question = """
Given a set of letter grades, output the GPA (grade point average) of those grades.

Key and examples:

A = 4 grade points
A- = 3.7 grade points
B+ = 3.3 grade points
B = 3 grade points
B- = 2.7 grade points
C+ = 2.3 grade points
C = 2 grade points
C- = 1.7 grade points
D+ = 1.3 grade points
D = 1 grade point
D- = 0.7 grade points
F = 0 grade points
$ calculateGPA(['A'])
$ 4

$ calculateGPA(['F', 'F', 'F'])
$ 0

$ calculateGPA(['A', 'A-', 'B+', 'B', 'B-'])
$ 3.3

$ calculateGPA(['A', 'B+', 'C-', 'A'])
$ 3.3

"""

import re

def calculateGPA(grades):
    total = 0
    T = { 'A' : 4, 'B' : 3, 'C' : 2, 'D' : 1, 'F' : 0 }
    Z = []
    for grade in grades:
        Z.append(grade)
    all_grades = ''.join(sorted(Z))
    for k in T.keys():
        all_grades = re.sub(k, str(T[k]), all_grades)
    for ch in all_grades:
        if ch == '-':
            total -= 0.3
        elif ch == '+':
            total += 0.3
        else:
            total += int(ch)
    
    print(str(total / len(grades)))

calculateGPA(['A'])
calculateGPA(['F', 'F', 'F'])
calculateGPA(['A', 'A-', 'B+', 'B', 'B-'])
calculateGPA(['A', 'B+', 'C-', 'A'])