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

Alejandro Byrne
Alejandro Byrne
2,562 Points
Posted by Alejandro Byrne
Alejandro Byrne
2,562 Points

Why doesn't my function work?

Hi, sorry, another question. I tried to get the course by seeing if the topics were in union instead of just if topics in course:. Help?

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(topics):
    result = []
    for topic in topics:
        for course_key, course in COURSES.items():
            if topic in course:
                result.append(course_key)
    return result

def covers_all(topics):
    result = []
    for course_key, course in COURSES.items():
        if topics in topics.union(course):
            result.append(course_key)
    return result

1 Answer

Claudio Longato Jr
Claudio Longato Jr
4,318 Points
Claudio Longato Jr
Claudio Longato Jr
4,318 Points

I couldn't understand if you wanted to check if you're trying to check if the topic is in all courses. For example, you check if the topics 'integers', or 'Python' is in all courses.

I'm sending a working function that answers: Which of the topics (in the argument [list]) are present in all courses?

def covers_all(topics):

result = []

for topic in topics:
    # counter
    is_in_course = 0

    for course_key, course in courses.items():
        if topic in course:
            is_in_course += 1

    if is_in_course == len(courses):
        result.append(topic)

return result