/** * func: is_pareto_sorted() * desc: returns true if and only if the list is: * - STRICTLY INCREASING IN price AND * - STRICTLY DECREASING IN time * * REQUIREMENTS: * RUNTIME: linear in length of list n (i.e., O(n)). * * status: TODO * * COMMENTS: notice that because of the runtime requirement, you cannot simply do this: * return is_sorted() && is_pareto(); */