Here are two versions of fibonacci I thought of

```
def fibonacci( n )
  return  n  if ( 0..1 ).include? n
  ( fibonacci( n - 1 ) + fibonacci( n - 2 ) )
end
puts fibonacci( 5 )

def fib(n)
  if n == (0..1)
    return n
  elsif 
    return fib(n-1) + fib(n-2)
  end
end
puts fib(5)

```

Why doesent the second fib(n) work?