Write a robot simulator.
A robot factory's test facility needs a program to verify robot movements.
The robots have three possible movements:
<ul>
<li>turn right</li>
<li>turn left</li>
<li>advance</li>
</ul>
Robots are placed on a hypothetical infinite grid, facing a particular direction (north, east, south, or west) at a set of {x,y} coordinates, 
e.g., {3,8}, with coordinates increasing to the north and east.
The robot then receives a number of instructions, at which point the testing facility verifies the robot's new position, and in which direction it is pointing.
<ul>
<li>The letter-string "RAALAL" means:
<ul>
<li>Turn right</li>
<li>Advance twice</li>
<li>Turn left</li>
<li>Advance once</li>
<li>Turn left yet again</li>
</ul>
</li>
<li>Say a robot starts at {7, 3} facing north. 
Then running this stream of instructions should leave it at {9, 4} facing west.</li>
</ul>

Robot Simulator