Why is the second and nested loop necessary?

[thevizslacoder]

Help with Step 19 in Python 3 - String Methods - Project Thread Shed please …

https://www.codecademy.com/courses/learn-python-3/projects/thread-shed

My code for Step 19 is as follows …

I have compared it with the Solution in the Project Walkthrough video. But I don’t understand why the second and nested loop is necessary. Why doesn’t my code suffice? If I were to narrate my code with the test color of “white”, I’d say, "for the variable “white” that is assigned to the color argument, every time I loop through the list and come across a “white,” add +1 to the counter.

[janbazant1107978602]

@thevizslacoder

def color_count(color):
  counter = 0
  for color in thread_sold_split:
    counter += 1
  return counter

If color happens to be "white", you want to add 1 to the counter (increment counter) only if "white" matches entry in thread_sold_split.

Your code doesn’t check whether "white" matches entry in thread_sold_split, it only iterates through thread_sold_split and adds to counter for any entry in thread_sold_split (which would end up making counter the same as len(thread_sold_split) ).

for color in thread_sold_split:
iterates through all the stuff (elements) in the thread_sold_split array, and assigns each element to the variable color
(Whatever was in color previously, like "white", is overwritten, I think.)

You’d need an if inside the loop to check whether that element of the array matches the argument of that function, and take the appropriate action if it matches.