Recursion

• A function that call itself until a problem is solved. The point at which the problem is solved is called base case.
• It’s good to think about function calls as a stack. Even the segment of memory that is used for function calls is also called stack.
• Always have well-defined base case.
• Keep in mind that some recursive problems can be implemented as iterations.
• Recursion can be broken down into three steps:
  • Pre: Operations before recursion.
  • Recursion: The function call.
  • Post: Operations after recursion.
• Tail Call Optimization:
  • The compiler or interpreter transforms a recursive function into a loop in order to avoid getting a stack overflow. You’ll get n infinite loop if you mess up though.