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

Hjalte Bøgehave
Hjalte Bøgehave
6,367 Points
Posted by Hjalte Bøgehave
Hjalte Bøgehave
6,367 Points

Can't get covers_all to work and don't know why

When i walk through the cover_all code it really should work in my head. Can anyone spot my mistake?

Thanks!

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):
    finish = []

    for keys, values in COURSES.items():
        if topics & values:
            finish.append(keys)
    return finish

def covers_all(topics):
    finish = []

    for keys, values in COURSES.items():
        if topics >= values:
            finish.append(keys)
    return finish

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

The goals of "covers" and "covers_all" are pretty similar except that in "cover" you only care that some overlap exists, but in "covers_all" the overlap must be the same as the agument set.