Exercise: Fibonacci closure

Let's have some fun with functions.

• Implement a fibonacci function that returns a function (a closure) that returns successive fibonacci numbers (0, 1, 1, 2, 3, 5, ...).

Note

We had to add a variable oldA to track the older value of variable a so that we could start the sequence from 0 rather than starting from 1

That is 0,1,1,2,3,5,8,13,21,34,55,89,144

Instead of 1,1,2,3,5,8,13,21,34,55,89,144,233

Output