Complete Fib

public int fib( int n )
{
  if ( n == 1 ) 
    return 1;
    
  else if  ( n == 2 ) 
    return 1;
    
  else
    return fib( n-1 ) + fib( n-2 );
}

It may worry you that the code for fib(int n) uses fib(n-1) and fib(n-2). This is fine. Look at the math-like definition. Play with it until you understand it. The program says the same thing but uses a different language (Java) to say it.

It is the job of the Java system to make sure that you get the computation that you ask for.