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Nikhil Rai
15,391 Pointsmy program is not going further please help!!
Hi,
I got a new challenge in Pythom collection and I did the program (it runs and gives the right result)... however the system is not letting me move forward saying list doesn't have right items.
messy_list = [5, 2, 1, 3, 4, 7, 8, 0, 9, -1]
# Your code goes below here
clean_list = messy_list[:]
clean_list.sort()
silly_list = messy_list[len(messy_list)+1:0:-3]
1 Answer
Gunhoo Yoon
5,027 PointsWhy would you want to do messy_list[len(messy_list)+1:0:-3]
When you can just do messy_list[::-3]
messy_list[len(messy_list)+1:0:-3] returns [-1, 8, 3]
messy_list[::-3] returns [-1, 8, 3, 5]
messy_list[len(messy_list)+1:0:-3] This translates to 3 steps backward from index 11 to index 1. Index 11 does not exist but in this case Python won't complain and just use last item which is -1 and since it stops before index 0 your list will look like [-1, 9, 0, 8, 7, 4, 3, 1, 2] which misses item 5.
Nikhil Rai
15,391 PointsNikhil Rai
15,391 PointsOoops!! Didn't notice this simple thing .... thanks a lot for help!! Cheers