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

David Luo
David Luo
1,214 Points
Posted by David Luo
David Luo
1,214 Points

Set object: intersecting sets of topics, return course title. Not getting right results, but logically seems to work

Any suggestions? Perhaps don't use a list comprehension?

or is method issubset incorrectly used? how about s & topics == s to achieve the same thing?

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 covers1(s):
    return [course for course, topics in COURSES.items() if s & topics == s] 
"""

def covers(s):
    return [course for course, topics in COURSES.items() if s.issubset(topics)]
David Luo
David Luo
1,214 Points
David Luo
David Luo
1,214 Points

finally figured it out.

apparently I thought s.intersection(topics) is the same as s.issubset(topics)

1 Answer