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Python

Peter Gess
Peter Gess
16,553 Points
Posted by Peter Gess
Peter Gess
16,553 Points

Not able to get the right result comparing two sets

I am not sure where my code is wrong...please assist!

Great work!

OK, let's create something a bit more refined. Create a new function named covers_all that takes a single set as an argument. Return the names of all of the courses, in a list, where all of the topics in the supplied set are covered.

For example, covers_all({"conditions", "input"}) would return ["Python Basics", "Ruby Basics"]. Java Basics and PHP Basics would be excluded because they don't include both of those topics.

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_all(args):
    result = [] 
    for key, value in COURSES.items():
        if args & COURSES.values():
            result.append(value)
    return result

3 Answers

Cheo R
Cheo R
37,150 Points
Cheo R
Cheo R
37,150 Points

You're close.

if args & COURSES.values():

COURSES.values() is not a set (type(COURSES.valuess()) gives dict_values). But you can do:

if args & value

Because type(value) is a set.

Then all you need to swap out is what you append to your result (you want the course name).

Peter Gess
Peter Gess
16,553 Points
Peter Gess
Peter Gess
16,553 Points

Thanks Cheo.

I modified my code but still not passing...Shouldn't I be appending the key?

def covers_all(args):
    result = []
    for key, value in COURSES.items():
        if args & value:
            result.append(key)
    return result
Cheo R
Cheo R
37,150 Points
Cheo R
Cheo R
37,150 Points

My mistake, looks like

if args & value

Is true if at least one of the args is present in value. So all you'd have to do is to check if both are present.

Peter Gess
Peter Gess
16,553 Points
Peter Gess
Peter Gess
16,553 Points

Yes I have that...so why isn't it working?

Cheo R
Cheo R
37,150 Points
Cheo R
Cheo R
37,150 Points

What does your current code look like now?

Peter Gess
Peter Gess
16,553 Points
Peter Gess
Peter Gess
16,553 Points

Thanks for you continued help Cheo. I found another implementation that used difference and it passed...sometimes these code challenges can be really finicky.