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

Posted by sabrina watson
sabrina watson
1,398 Points

How come this is not passing?

def covers(par): lst = [] for k in COURSES.keys(): if par.issubset(COURSES[k]): lst.append(k) return lst

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(par):
    lst = []
    for k in COURSES.keys():
        if par.issubset(COURSES[k]):
            lst.append(k)
    return lst

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

You're close, but a set is a subset of another only if all of its elements are in common with the other set, so that test is too specific for this particular task.

The challenge wants to see a list where the sets "overlap". This means where the sets have any element(s) in common.