Niko's Project Corner

Bruteforcing Countdown numbers game with CUDA

Youtu­ber An­other Roof posed an in­ter­est­ing ques­tion on his video "The Sur­pris­ing Maths of Britain's Old­est* Game Show". The chal­lenge was stated in the video's de­scrip­tion: "I want to see a list of the per­cent­age of solv­able games for ALL op­tions of large num­bers. Like I did for the 15 op­tions of the form {n, n+25, n+50, n+75}, but for all of them. The op­tions for large num­bers should be four dis­tinct num­bers in the range from 11 to 100. As I said there are 2555190 such op­tions so this will re­quire a clever bit of code, but I think it’s pos­si­ble!". His ref­er­ence Python im­ple­men­ta­tion would have taken 1055 days (25000 hours) of CPU time (when all four large num­bers are used in the game), but with CUDA and a RTX 4080 card it could be solved in just 0.8 hours, or 31000x faster!