Shape recognition

One of the prerequisites for keeping an accurate running card count in your head is to become very conversant with the various hand shapes, so you don't even have to think about them:

4333    4432    4441

5332    5422    5431    5440    5521    5530

6322    6331    6421    6430    6511    6520    6610

7222    7321    7330    7411    7420    7510    7600

8221    8311    8320    8410    8500

9211    9220    9310    9400