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

vikas Rai
vikas Rai
9,703 Points
Posted by vikas Rai
vikas Rai
9,703 Points

What is wrong with my code

Please help me to identify whats wrong here

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(s):
    var=[]
    while s:
        myVar=s.pop()
        for i in COURSES:
            if myVar in COURSES[i]:
                if i not in var:
                    var.append(i)
    return var

1 Answer

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

It looks like you're building a list of topics that overlap, but the challenge wants you to build a list of courses that have any topics that overlap. Remember the topics are the values, and the courses are the keys.

Also, while the strategy you're working on can be made to work, you can get the desired results without nested loops if you use the set operations that were introduced in that last video lesson.