Iteration for iteration in a list

Question

Let's say I have 2 lists and a variable:

Name = "Siler City"
List1 = ["Frank", "Beth", "Jose" "Pieter"]
List2 = ["Red", "Green", "Blue", "Purple"]

This is a simple illustration of a complex problem and there is a reason I don't want to create a dictionary. These must be 2 separate list. What I want is to iterate through List1[0] and List2[0], etc... at the same time. So my desired results would be

"The Red house is owned by Frank", "The Green house is owned by Beth", "The Blue house is owned by Jose,"

etc...Why won't the below work and what is a better strategy?

for item in List1:
    if Name == "Siler City":
        for color in List2:
            print("The {} house is owned by {}".format(color, item))

You iterate through List2 for each item in List1 (because the second for loop is inside the body of the first for loop). — folkol, Sep 04 '18 at 19:25

Nick Dima · Accepted Answer · 2018-09-04T19:33:09.000

2

You can zip your lists together to iterate over both

for list1_elm, list2_elm in zip(List1, List2):
  pass # Remove pass when you add your print statement
  # Do things Here

edited Sep 04 '18 at 19:33

answered Sep 04 '18 at 19:24

Nick Dima

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@mad_ Thanks for the heads up! was trying to leave the rest up to OP but I can see how that might be confusing. Added in a place holder! – Nick Dima Sep 04 '18 at 19:27
Note, it is *still* syntactically incorrect... you'd need a `pass` at least – juanpa.arrivillaga Sep 04 '18 at 19:31
@juanpa.arrivillaga Thank you! Adding a pass now – Nick Dima Sep 04 '18 at 19:33
This code works! Thanks! – gwydion93 Sep 04 '18 at 19:54

score 2 · Answer 2 · answered Sep 04 '18 at 19:24

2

Use zip:

for item, color in zip(List1, List2):
    print("The {} house is owned by {}".format(color, item))

answered Sep 04 '18 at 19:24

Will Vousden

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Disregard last comment. This is the most succinct answer. Thanks. – gwydion93 Sep 04 '18 at 19:53

Iteration for iteration in a list

2 Answers2