The goal of this exercise is to experiment with an object pool.The first step is to implement a simple data type List. A List is either Nil or is a Cons holding an object and a List. Conses are also called list cells. This is exactly the abstract data type "linked list" that you should have learned in CS162 or equivalent.
The second step is to design and implement a pool for the list cells. Obviously, the pool must both accept list cells released to the pool and must supply a list cell upon request. The requested list cell is either fetched from the pool, if any is available, or constructed from scratch if none is available in the pool. The pool should keep track of how many list cells are constructed, recycled, and held into the pool.
The last step is to code a test harness for your pool. The harness makes a number of randomly chosen calls to the pool. A call either requests a cell from the pool or release a cell to the pool, if any is available to the harness.