Here is my exam, I did the cash-machine test.
https://github.com/cenon4dno/developers/tree/master/want-to-be-clickbus/cash-machine/index.php
No specification so I did a simple PHP implementation.
Basic PHP and Apache setup.
Cross-browser compatible: FF, Chrome, IE11 and Safari. Other browser not tested but assumed working.
Just drop in your Apache DocumentRoot and run index.php.