What's the Length of the Missing List?

Create a function that takes a list of lists and return the length of the missing list.

Examples

find_missing([[1], [1, 2], [4, 5, 1, 1], [5, 6, 7, 8, 9]]) ➞ 3

find_missing([[5, 6, 7, 8, 9], [1, 2], [4, 5, 1, 1], [1]]) ➞ 3

find_missing([[4, 4, 4, 4], [1], [3, 3, 3]]) ➞ 2

Notes

• Test input lists won't always be sorted in order of length.
• If the list of lists is None or empty, your function should return False.
• If a list within the parent list is None or empty, return False.
• There will always be a missing element and its length will be between the given lists.