BIG_DECIMAL!!!!!)

You don't have to use Integer.MAX_VALUE here.
I'm not sure about efficiency but it makes more sense to assign the variable smallest to args[0].

Im new with the programming, just want to now if i understand this correctly, getNumericValue is checking for the first char from the string and return string depending on the number?

若测试用例有2位数字的话，这个答案就不适用了

is not that obsolete since i got similar code, but I failed tests that have 2 digits.

Well... Sorry to say that, but... TESTS ARE SHIT! X-( And description isn't good either.

• description is misleading: listing 1 in the divisors, but not counting them as divisors (wtf!? Choose your side, man!)
• need random tests
• need checks on boundaries!!! the number of divisors evolves in a very erratic way, so using arbitrary values of n as it is for now allow implementations counting the divisors in a wrong way to pass: I didn't see the trouble with 1 at the beginning and failed on the small tests but passed all all the other ones while I was off by one.

// I would give a 7kyu ranking..
When facing some cases like avg. 5kyu. power avg. 6kyu., I am likely to prefer the former when there are many rankings(>= 10) and the latter when there are less solutions...
If you say so, changed.

There are no performance requirements at all?

Then this is not 5kyu. More like a 6kyu.

This kata needs a performance version. That would be fun. :)

It seems there's a problem with the submission tests here. The last test asks for the first number with 10 factors and expects a return of 120 but if you print n it shows that it actually asks for 9 factors and and a return of 120 meaning the algorithm for solving this will return an incorrect value.

You are right. I am wrong. Apologies.

Did you try testing )(() on this code yourself? It should return false right after the first ) is read.

This and many other apparently "best practice" solutions are just plain wrong. Only checking numbers match is not enough. Consider )(() - it is not balanced yet this code will say it is.

i is a bad name for a variable. If used at all, it is used for an index and not for the value.

+BC from me. I like the iterating via for (char) instead of counting an index, but I think toCharArray() is an additional copy of the input, so it comes wih a cost.

Minor improvement: you could simply write return count == 0; which just happens to return the resulting boolean. No need for explicitly checking it for true/false here.