This one is a bit tougher so don't feel bad if you don't finish. Again: the point is to demonstrate your thinking process and that you ask enough questions and think things through before you write any code.
Here’s the question:
You have k lists of sorted integers. Find the smallest range that includes at least one number from each of the k lists.
Here's some sample code
// For example, list1 = [4, 10, 15, 24, 26]; list2 = [0, 9, 12, 20]; list3 = [5, 18, 22, 30];