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Python Python Collections (2016, retired 2019) Sets Set Math

Ashley Keeling
Ashley Keeling
11,476 Points
Posted by Ashley Keeling
Ashley Keeling
11,476 Points

i don't know how to do this question

I am not sure about the second part of this challenge

sets.py 
COURSES = {
    "Python Basics": {"Python", "functions", "variables",
                      "booleans", "integers", "floats",
                      "arrays", "strings", "exceptions",
                      "conditions", "input", "loops"},
    "Java Basics": {"Java", "strings", "variables",
                    "input", "exceptions", "integers",
                    "booleans", "loops"},
    "PHP Basics": {"PHP", "variables", "conditions",
                   "integers", "floats", "strings",
                   "booleans", "HTML"},
    "Ruby Basics": {"Ruby", "strings", "floats",
                    "integers", "conditions",
                    "functions", "input"}
}

def covers(st):
    sets=[]
    for key, value in COURSES.items():
        if value & st:
            sets.append(key)
    return sets

def covers_all(set1):
    set2=[]
    for value in COURSES.items():
        if value & set1:
            set2.append(key)
    return set2

2 Answers

Gerald Wells
Gerald Wells
12,763 Points

So the trick here is, they expect you to go do research on set()....

def covers(course_query):
    return [ k for k,v in COURSES.items() if v & course_query]

def covers_all(course_query):
    return [k for k,v in COURSES.items() if course_query.issubset(v)]
Flore W
Flore W
4,744 Points
Flore W
Flore W
4,744 Points

Actually, another way to do it in the line of how you solved it in the first part is:

def covers_all(set1):
    list1 = []
    for key, value in COURSES.items():
        if value & set1 == set1:
            list1.append(key)
    return list1