this one is should be the top solution

this is probably the fastest solution, possibly because it does not use the ** (square) operator. I compared these top two solutions using timeit

used timeit to compare the performance of your solution with the top two above, and it outperformed them

have heard coders criticize the general use of generic for loops, but timeit has convinced me that my solution is performant—after comparing it with three other solutions.

have you used timeit to compare the performance of your Counter() solution with this one? I personally believe that your solution could be 10X slower.

[[]] <-- nothingburger

thanks for bringing this up. actually a 0 dimensional matrix because it fails to contain any values. it is an empty shell; a random tests byproduct for frustration purposes. would help to see this specific empty matrix in standard tests.

agreed, because the listcomp's list gets stored in memory. generator is preferred.

computers are mathematical by default, so you could actually cut the kata creator some slack. in other words, the kata is in the coder's mathematical wheelhouse.

yea, and if less than 25% of the coders were successful, then this certainly is NOT a 7 kyu. 10,000 annoyed coders is proof.