Same thing happened to me. The example tests didn't have negative numbers, but the random numbers all have negative numbers. So just have to account for negatives.

You didn't provide any solution here. Please paste your solution in the solution link, then maybe we can help

Can anyone look at my solution and tell my why all the example tests pass, but when i run the attempt only like 20 out of 100 pass?

use str.upper & str.lower will solve Ur Problem

I tried a few solutions and they worked fine. I don't understand your problrm:-(

Same here...

Same here! very weird

Actually, your code is failing on abcdeaB which should return 2 (["a", "b"]) but your code is returning 1 (["a"]). This is because you need to take in the uppercase and the lowercase alphanumerical character being the same - the casing shouldn't matter.

Weird!-)

client might not care but the next developer after you would. lol.

When I try my solution in irb it works correctly, when i run the tests here, random letters get all caps. eg. A-Bb-Ccc-Dddd-EEEEE-Ffffff.
not sure why though