Here you are guaranteed to get the unique numbers only in the array.

Not sure which language you use but in JS it is not expecting an empty array.
This is the test:

var tests = [
    {
      "input": "A1",
      "expected": ["A2", "A3", "A4", "A5", "A6", "A7", "A8", "B1", 
    "B2", "C1", "C3", "D1", "D4", "E1", "E5", "F1", "F6", "G1", "G7", "H1", "H8"]
    },
    ...

Hey, does the $ have any special meaning?

Sometimes you just make it work and then think of chaning the style :)

may be a stupid question of a JS beginner but - why there is 'i < data.length' instead of 'i < data.length - 7'?

Java - change the class name and method name ffs

I dont really get it - why there is "b+1 > s.length()" in if statement? Why "+1", not "b"?

hey, why arent you using 'f' and 'wm' indexes in 'goup by' and 'order by'?

yep, happend to me while ago :)

I made it kind the same but in your solution
this: (ab+c>max)
Is the same as this: ((ab)+c>max)
parenthesis make no difference here ;)