1. Introduction
2. Recursion
3. Cases
4. Further Examples
5. Checkpoint 1
6. Why Recursion?
7. Extra parameters
8. Checkpoint 2
9. Reflection

Checkpoint 2

1. Using listAllFiles as a guide, write a method that has one File argument: if the argument is a directory, the method returns the total number of files below it. If the argument represents a file, the method just returns 1.

   public static int countFiles(File f) { ...
   

2. A mason is using rectangular bricks to make a walkway. He has bricks that are 3 feet long and bricks that are 1 foot long. If the walkway is a total of n feet long, how many different ways are there to lay out bricks for the walkway? For example, if n is 5, there are four possibilities:

   

   Your method should look like this:

   public static int countPatterns(int n)
   {
     // TODO
   }
   

   Tip: What if n is 100? He can start with a 1-foot brick (and then do 99 feet more) or else he can start with a 3-foot brick (and then do 97 feet more).