CS2
Recursion
7
Components of recursive definition
• Every valid recursive method definition needs two parts –
the base case and the recursive part
• The base case gives the
value that the method should return for some specified parameters
– Usually the base case represents some sort of “trivial” case,
such as a zero parameter or an empty list etc.
• The recursive part expresses
the value to be returned in terms of another call to the same method, but
with different parameters
– To work correctly, the “different parameters” must be closer to
the base case (in some sense)