How strict do you want the checking to be? The initial algorithm accepts (1),(2, 3) as valid input, as well as 1,2,3)))))) etc.

You might want to consider changing your regex to make it more strict, as there are a lot more than just your example input (1, 2, 3) that gets excepted.

How strict do you want the checking to be? The initial algorithm accepts (1),(2, 3) as valid input, as well as 1,2,3)))))) etc.

You might want to consider changing your regex to make it more strict, as there are a lot more than just your example input (1, 2, 3) that gets accepted.

How strict do you want the checking to be? The initial algorithm accepts (1),(2, 3) as valid input, as well as 1,2,3)))))) etc

How strict do you want the checking to be? The initial algorithm accepts (1),(2, 3) as valid input, as well as 1,2,3)))))) etc.

You might want to consider changing your regex to make it more strict, as there are a lot more than just your example input (1, 2, 3) that gets excepted.