Add split number solution

Signed-off-by: Aniket Pant <me@aniketpant.com>
Add solution to uk-and-us-2

Signed-off-by: Aniket Pant <me@aniketpant.com>
Improve old code

Signed-off-by: Aniket Pant <me@aniketpant.com>
Add new solutions

Signed-off-by: Aniket Pant <me@aniketpant.com>