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Python Introducing Lists Build an Application Multidimensional Musical Groups

keith rezendes
keith rezendes
4,459 Points

multi-dimensional list using join

how to flatten a 2D list using join method?

musical_groups = [
    ["Ad Rock", "MCA", "Mike D."],
    ["John Lennon", "Paul McCartney", "Ringo Starr", "George Harrison"],
    ["Salt", "Peppa", "Spinderella"],
    ["Rivers Cuomo", "Patrick Wilson", "Brian Bell", "Scott Shriner"],
    ["Chuck D.", "Flavor Flav", "Professor Griff", "Khari Winn", "DJ Lord"],
    ["Axl Rose", "Slash", "Duff McKagan", "Steven Adler"],
    ["Run", "DMC", "Jam Master Jay"],
# Your code here
for i in range(len(musical_groups)):
    for j in range(len(musical_groups[i])):
        print(musical_groups[i][j] + ',')

2 Answers

Cooper Runstein
Cooper Runstein
11,850 Points

What you're attempting may work in a real world situation, but not for the way this practice problem is set up. Also notice that you're printing only a comma, not a comma and a space. Using join is the more pythonic practice, shown below.

Part 1

for group in musical_groups: #for each group in musical_groups
    print(', '.join(group)) #print a string created by joining each element in the group

Part 2

for group in musical_groups:
    if len(group) == 3: #if and only if the group has 3 members (the list is length 3)
        print(', '.join(group)) #print the joined string