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Python Introducing Lists Using Lists Multidimensional Lists

Posted by Aizah Sadiq
Aizah Sadiq
2,435 Points

Why do we put week_number += 1

What does week_number += 1 do

2 Answers

Mark Sebeck
MOD
Mark Sebeck
Treehouse Moderator 37,905 Points
Mark Sebeck
Mark Sebeck
Treehouse Moderator 37,905 Points

It takes the value stored in week_number and adds 1 to it then stores the new value in week_number. It’s the same as week_number = week_number + 1

Piotr Sochaczewski
Piotr Sochaczewski
13,038 Points
Piotr Sochaczewski
Piotr Sochaczewski
13,038 Points

I would like to know - why there isn't an infinity loop? ...

  • Week #4: $0
  • Week #5: $0 and so on?

This is what I don't get - why the program stopped :) (It's good but why?) I ask because in JS we should make some condition like i=0, i < travel_expenses.length and i+=1 but in python, we don't have any condition just +=1

Mark Sebeck
Mark Sebeck
Treehouse Moderator 37,905 Points
Mark Sebeck
Mark Sebeck
Treehouse Moderator 37,905 Points

Hi Piotr. Good question. It is because the for in loop automatically loops through the list or array. In this case the i+=1 is only incrementing i to print the week number.