These two functions each return an array, which contains a sequence of intgers; if n = 0, then they return an empty array, and if n = 1 they return a single value, [1]. However, if n is larger, they return a sequence that counts through the nubmers 1 to n. In climbUp(), the sequence simply counts up; in climbDownUp(), it starts at n, counts down to 1, and then counts back up to n. For example, if n = 4, then annoying climbUp() will return [1,2,3,4], while annoying climbDownUp() will return [4,3,2,1,2,3,4].