I was going through the guide on this thread, and I was stuck on the problem 'Secret Cow Code' here: USA Computing Olympiad
I was able to write the code using the solution on the USACO website, but I don't understand how this snippet specifically works:
while(2*length <= index) {length *= 2;}if(length == index) {return parse(s, length-1);}return parse(s, index - length - 1);
Thanks!