Sample tests passed. After btn "Attempt": SyntaxError: Invalid regular expression: /^$.|?*+()[]{}/: Nothing to repeat

(JS) It is not my expression. What is wrong?

The first number is multiplied by 1, the second number is multiplied by 3, the third by 1, etc. There are 1 and 3, not "or". Maybe there’s something I’m not considering.

I consider, that the multiplication condition is incorrectly stated in point 4 ('1 or 3' Why?). check_digit = 9*1 + 7*3 + 8*1 + 1*3 + 8*1 + 5*3 + 3*1 + 2*3 + 6*1 + 1*3 + 5*1 + 8*3

I do not understand. In the first test 4 parameters that are defined correctly are not one, but 4 parameters. In other tests the values are close to what is required. I am in a deadlock.

Test Passed: Value == '[15, 135, 49, 18]'
Expected: '[12, 133, 18, 44]', instead got: '[12, 148, 58, 36]'
Expected: '[20, 129, 41, 57]', instead got: '[21, 123, 58, 12]'
The first test passed. I can assume, that problem in rounding. Please, specify at which step the rounding?

Then 'a12' must be "VALID".

Why? 'a12' , 'INVALID' (JS)

I wrote my solve with used methods of string without loops. Have solutions any limitations? Samples tests is rigth, but then: RangeError: Invalid count value. So litlle additional tests, difficult to investigate.

After pressing the test button A6C2E5Z9A4.-F%8.08.- true. After pressing the attempt button A6C2E5Z9A4.-F%8.08.- false. Why? JS.

Ok. Thanks for the answer.

Sample Tests "Should work for under 7 days:" and Random tests probably contain error for JS.

I did it.

Cool. Find out how it works.
strCount('ooooodoodoodooo', 'd')
[ 'ooooo', 'oo', 'oo', 'ooo' ]
3

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