Create a function that takes an array and returns the number of ALL elements within it (including those within the inner-level array(s)).
deepCount([1, 2, 3]) ➞ 3
deepCount([[1], [2], [3]]) ➞ 6
deepCount(["x", "y", ["z"]]) ➞ 4
deepCount(["a", "b", ["c", "d", ["e"]]]) ➞ 7
In the examples above, notice how the sub-arrays within the main array count as an element as well as the elements within that sub-array.