erikprice / little-lost-robot

Can you help the robot escape the maze?

Little Lost Robot

A Javascript programming challenge.

Can you help the robot escape the maze?

Version 0.1 BETA

Getting Started

• Fork and clone this repo.
• Install NPM and NodeJS.
• In the root directory, run npm install, then node app.js to start the server
• Browse to http://localhost:3003
• Read on for details!

Objective

The object of this challenge is to steer a robot out of a 2-D maze. The maze is a grid of squares, some of which are filled by walls. If your robot moves out of the maze, you win. If you steer the robot into a wall, you fail. If your code throws an error, you fail. If there is no way out of the maze, you should power down the robot and send up a flare.

Framework

You accomplish this objective by programming a guidance system for a new robot type. A robot's guidance system consists of one function, the steer function. The steer function is called when the robot moves into a square. When the steer function gives up control by returning, the robot will move, unless the steer function has shut down the robot's motor, causing it to stop moving. Your steer function should shut down the robot's motor only if you are sure that there is no escape route from the maze. Otherwise, your steer function must rotate the robot to face an empty square. Your robot is very fragile; if it moves into a wall, it is destroyed!

The files in ./robots are sample implementations. Add your implementation to this folder. You may use ./robots/template.js, or any of the others, as a template.

Robot API

The guidance system has only limited access to the robot's other systems, which include a forward-facing sensor, a steering column, and an unlimited supply of "tokens" that the robot may drop from its undercarriage. These functions are methods of the robot object, accessable in the steer function via this. The API is described below. There is no way for the robot to examine the maze beyond its limited scope.

isFacingWall()

Self-explanatory. Returns true or false.

rotate(a)

Rotate the robot a times 90 degrees. Negative values of a rotate in one direction; positive in the other. Return the robot, for chaining.

dropToken(token)

The robot drops a token into the square it currently occupies. token may be any value. Any prior token value in the square is lost. Return the robot, for chaining.

tokenHere()

Return the token found in the current square, or undefined if there is none.

tokenAhead()

Return the token found in the square that the robot is facing, or undefined if there is none.

(Note: modifying the token value returned by this function in place, if possible, is contrary to the spirit of this challenge! Instead, let the robot move into the space and drop a new token.)

TODO: restrict token types in dropToken.

quit()

Shut down the robot's motor! This is the way to declare that the maze has no way of escape, which is the only way to "win" the challenge in the case of a hopeless maze.

Good luck!