Displaying part of number with brackets

So I'm writing code for math assignment i have to represent number from variable the following way: Let's say that's the number from variable A : 18,223443934844. And that how it should print like : 18,223(443934844). Numbers in the brackets are supposed to be the repeating part of the numbers after the decimal comma.

Had the idea to put every element of the number in array and then put the brackets whenever necessary but don't really know how to do it.

I'd appreciate every advice.