Staircase

![image](https://cloud.githubusercontent.com/assets/218289/4017906/8d9af5be-2a45-11e4-9b92-469ee995f098.png)

Voor | Na
---|---
![image](https://cloud.githubusercontent.com/assets/218289/4020711/832e3f20-2aca-11e4-9df9-878496263997.png) | ![image](https://cloud.githubusercontent.com/assets/218289/4020712/8e606ac6-2aca-11e4-87bb-f7cc7a458602.png)