which instantly makes it harder to read, so lets dont do that.

@sean_little the description states: 'If the list is made up of only negative numbers, return 0 instead.' The 'max' would end up being a 0 and thus 0 is returned.

The list can also be replaced with the generator expression directly

approved

Btw,I'am a bit confused. what about all the numbers in the arr are negtive?

agree, elif will be better

.

Yeah, I gave it clever, since it only loops through the array once to find the answer. The syntax might not be beautiful, but the logic is.

I think the code complexity is what's important here.
Even though it's not written in the most beatiful way, complexity is very low.

However shadowing the built-in fucntion? definitely not the best practise.

Good catch, thanks.

I absolutely agree. Thanks for the comment. Even better, I can use enumerate instead of index:

tobase64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
frombase64 = {v: i for i, v in enumerate(tobase64)}

@lawg is right, there are a few more reasons why this isn't 'best practice'.

Here are the warnings shown on PyCharm for this solution by @RM84:

• PEP8: Function name should be lowercase (caused by katas author, not @RM84)
• PEP8: Missing whitespace after ','
  • Line 2: 'max,curr' & '0,0'
• PEP8: Missing whitespace around operator
  • Line 2: '='
  • Line 4: '+='
  • Line 5: '<' & '='
  • Line 6: '>' & '='
• PEP8: Multiple statements on one line (colon)
  • Line 5
  • Line 6
• Shadows built-in name 'max'

You could also replace the line max,curr=0,0 with something like maximum = current = 0.