Fibonacci's Bunnies

The famous bunny sequence: each month's count is the sum of the previous two. 1, 1, 2, 3, 5, 8… 🐇

You get n. Print the n-th bunny number (the 1st and 2nd are both 1). Two running variables are all you need — remember dual-tracking from your very first unit?

Example:

Input: n = 7 Output: 13

The sequence runs 1, 1, 2, 3, 5, 8, 13 — the 7th number is 13.