Good code is its own best documentation. As you're about to add a comment, ask yourself, 'How can I improve the code so that this comment isn't needed?' Improve the code and then document it to make it even clearer. Steve McConnell
Coin Change is the problem of finding the number of ways of making changes for a particular amount of cents, n, using a given set of denominations d1,… dn.
General coin change that keeps track of coins: [5, 5]