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Python

Posted by Jesse Davidson
Jesse Davidson
647 Points

For loop issue

Hi guys,

Can you please explain the last line of code in a bit more detail as I'm struggling to grasp this.

numbers = [0, 1, 2, 3, 4, 5] for number in numbers: numbers.remove(number) - #Struggling with this

1 Answer

Majid Bilal
Majid Bilal
3,558 Points
Majid Bilal
Majid Bilal
3,558 Points 
numbers = [0, 1, 2, 3, 4, 5]

for number in numbers:
    numbers.remove(number)

print(numbers)

It's simple, you are iterating through the list of numbers, in every iteration an element of the list gets assigned to the 'number', meaning in first iteration 'number = 0' and in second iteration 'number = 1' and so on. This number is then passed as the list index in the remove method so in first iteration numbers.remove(number=0) it removes the first index in the numbers that is '0' in second iteration numbers.remove(number=1) and remember we have removed the first index so the list now is [1, 2, 3, 4,5] which means now the we have '2' at index 1 so in next iteration '2' gets removed and we are left with a list [1,3,4,5] and at next iteration we have number = 2 and we have '4' at index 2 so 4 gets removed and we are left with [1,3,5].

Hope this clarifies it for you.