Sure, Got it! It was my mistake in interpreting the kata.

Python: You have a mistake in the test case number 8 ---> test.assert_equals(build_one_two_three().next.next.next, None, "Third node should should have 3 as data.") as you are referencing to the memory address and not to the data itself, thus an issue.

I think it should be ----> test.assert_equals(build_one_two_three().next.next.next.data, None, "Third node should should have 3 as data."). The test makes the entire test attempt to fail.

In your test cases:

matrix = [] ---> This is not 0x0 matrix, it should be [[]]
test.assert_equals(sum_diagonals(matrix), 0) ```

some solutions does not work until you format it to 0x0, the description is clear we work with a 2 dimensional array and not 1 dimension. Hence an issue.

May be you should try to re-think about to change your algorithm as It has too many loops to handle thus ineffective for huge array.

I just solved it in JS. My algorithm takes around 1000ms. I did not apply dynamic programming. I think if you know the answer, it real worth 6kyu or below.

Nice Kata. Can you change the name of the function to be similar? def shortest_path(topology, start, end): return 0 or shortestPath(topology, 'a', 'e')

Wow, thank you.

For the case of 999, the description is clear that for this kata you will be working with a four digit number. For the test cases, I have added more -1 results. Hope I understood you correctly.

I thought for this case 6174 was not the first 4 digit number given by Rachel. You enter the pin code after you finish all the iterations required and not after each iteration.

Got your point, already rectified. Thanks again

You test it, At the point you test it, means you have iterated/tested atleast once.

At first you don't know the code, you must test the given four digit number atleast once.
For the second, I need to add a note that, the code can't be formed by all 4 repeated digits. Thanks for observation

Nice kata!

I think if the kata has a number of alternative solutions you should not have limited the user to confine to your thinking.

Ofcourse more tests have been added, kindly optimize your codes.