Amidst all of this, two interpreted programming languages saw themselves being used the most: BASIC and APL, with the latter being IBM’s programming language of choice for its mainframes.

Petzold: Certainly coding is a great intellectual discipline ... torrid affair with an exotic language called APL. This was also in a corporate environment, early 80s probably.

I have had no prior APL experience. In fact ... In optimizing the runtime, I drew on what I knew about computers and programming languages in general.” The competition was launched 27th April 2009 ...