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Python Introducing Lists Using Lists Multidimensional Lists

Kayc M
Kayc M
12,593 Points

What if I wanted to sum it all together after iterating them?

How do I automate the script to give me a final value of 147.25

2 Answers

Mustafa Başaran
Mustafa Başaran
28,021 Points

Hi Kayc,

You may need a for loop within a for loop for this. Please follow the steps below.

# declare a total_sum variable and set it equal to zero
total_sum = 0

# iterate over travel_expenses list. On each iteration, t_e is a sublist within travel_expenses, right?   
for t_e in travel_expenses:
# now, iterate over t_e. This will give you each and every element within a sublist on that iteration.
  for i in t_e:
# add each element, i, to total_sum. 
    total_sum += i

# then, you will have every element summed up. 

#Yes, it is 147.25. 

I hope this helps.

Kayc M
Kayc M
12,593 Points

I looked it up on Google for a while and nothing. That's exactly what I was looking for, thank you.

Make sense. Thanks

travel_expenses = [
    [5.00, 2.75, 22.00, 0.00, 0.00],
    [24.75, 5.50, 15.00, 22.00, 8.00],
    [2.75, 5.50, 0.00, 29.00, 5.00],

print("Travel Expenses:")
week_number = 1
running_total = 0
for week in travel_expenses:
    weekly_sum = sum(week)
    running_total += weekly_sum
    print("* Week #{}: ${}".format(week_number, weekly_sum))
    week_number += 1

print("Your current total expenses are {}".format(running_total))