Bah one line of BBC basic. One line of incomprehensible BBC basic more like. When I was at school I implemented a game in three lines of spectrum basic. 5 if you wanted scoring. And it was readable. And it was the most popular computer game in the school by virtue of it being quicker to type than loading a tape, and being moderately entertaining. Just bound the cursor keys to the values in the line() function. The game crashed if the line went out of bounds :).
