Expected behavior:
<pre>
-
let t1 = (make-list 1 nil) in
let t2 = (make-list 2 nil) in
let t3 = (make-list 3 nil) in
count-leaves ta ~~> 6
count-leaves tb ~~> 6
count-leaves tc ~~> 6
-<pre>
+</pre>
#Write a function that counts the number of leaves.#