Write a generator function that returns a generator object which yields the fibonacci sequence.
The fibonacci sequence is defined by the relation Xn = Xn-1 + Xn-2.
The first few numbers of the series are 0, 1, 1, 2, 3, 5, 8, 13.
Example 1:
Input: callCount = 5 Output: [0,1,1,2,3] Explanation: const gen = fibGenerator(); gen.next().value; // 0 gen.next().value; // 1 gen.next().value; // 1 gen.next().value; // 2 gen.next().value; // 3
Example 2:
Input: callCount = 0 Output: [] Explanation: gen.next() is never called so nothing is outputted
Constraints:
0 <= callCount <= 50