Write a robot simulator.
A robot factory's test facility needs a program to verify robot movements.
The robots have three possible movements:
- turn right
- turn left
- advance
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.
- The letter-string "RAALAL" means:
- Turn right
- Advance twice
- Turn left
- Advance once
- Turn left yet again
- Say a robot starts at {7, 3} facing north. Then running this stream of instructions should leave it at {9, 4} facing west.
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Get PHPUnit.
% wget --no-check-certificate https://phar.phpunit.de/phpunit.phar % chmod +x phpunit.phar
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Execute the tests for an assignment.
% phpunit.phar wordy/wordy_test.php
Inspired by an interview question at a famous company.
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