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Python Introducing Lists Build an Application Multidimensional Musical Groups

gurveer aulakh
gurveer aulakh
2,800 Points
Posted by gurveer aulakh
gurveer aulakh
2,800 Points

multidimensional musical quiz help!!

PLs, help me solve this problem. I ran out of all the possibilities. pls, help y'all.

groups.py 
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 group in musical_groups:
    print(", ".join(group))
    if len(musical_groups) == 3:
        print(group)

2 Answers

Johannes Scribante
Johannes Scribante
19,175 Points
Johannes Scribante
Johannes Scribante
19,175 Points

Gurveer, if you look at your code and you go through it systematically, what is your code saying?

for group in musical_groups:

Loop through each item in musical groups. That would give us being through each iteration of the loop

    > ["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"]

Each item is therefore a list on its own.
Then you are saying

print(", ".join(group))

Now that we are currently looking at all of the lists in musical_groups, we will be printing the following

    > "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"

Only after you have printed all your lists (and nicely formatted) are you checking the condition to see if a group only contains 3 items.

That is where Henrik Christensen was trying to guide you.

# loop through musical_group
    # condition to check if group has 3 items
        # then print the formatted group
gurveer aulakh
gurveer aulakh
2,800 Points
gurveer aulakh
gurveer aulakh
2,800 Points

that what I did. I have a loop then if statement and after that print statement.

Henrik Christensen
seal-mask
.a{fill-rule:evenodd;}techdegree
Henrik Christensen
Python Web Development Techdegree Student 38,322 Points
Henrik Christensen
.a{fill-rule:evenodd;}techdegree
Henrik Christensen
Python Web Development Techdegree Student 38,322 Points

No, it's not what you're doing

# loop here
for group in musical_groups:
    # if group has 3 members
    if len(group) == 3:
        # print that group
        print(', '.join(group))