Not everybody is good at performing under pressure on problems that come with ambiguous artificially imposed rules that you have to guess. I remember solving a

Not everybody is good at performing under pressure on problems that come with ambiguous artificially imposed rules that you have to guess. I remember solving a problem that involved manipulating a list. There was an improvement to my algorithm that involved calling list.sort() before performing a slightly more efficient version of what I was doing. I didn't think calling built-in sorting algorithms was allowed. That's typically one of the implicit rules, until it's not, and you just have to figure out when it is and when it's not a rule.