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

Posted by Siddesh Gannu
Siddesh Gannu
3,565 Points

covers function not working

My code doesn't work in the editor but it works on my personal IDE. I tried changing the spaces to tabs. But it keeps telling me that it's not getting the right result for covers.

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

1 Answer

Steven Parker
Steven Parker
229,732 Points
Steven Parker
Steven Parker
229,732 Points

It's not your indentation. But the function should produce a list of classes where the topics overlap. By "overlap" they mean if it has any topics in common. But a subset only exists when the set has every topic in common with the other set. So this is not the right test for this function (it might be useful later, though!).

See if you can find a different method that will meet the specific needs of this function.

Siddesh Gannu
Siddesh Gannu
3,565 Points

Thanks, I used "if not isdisjoint(topics)" that worked for me

Steven Parker
Steven Parker
229,732 Points
Steven Parker
Steven Parker
229,732 Points

I assume you meant "if not topic.isdisjoint(topics):" — and very clever! :+1: I don't think I've seen that method used for this before.