Change in the existing solulion of Exercise18_02 of ch_18

[Sahilkumar19]

given solution is completely right ...but here is the more optimized solulion without using any loop after solving the recurrence relation of the fibonacci number we will get a direct formula to get the nth fibonacci term. On further solving the formula we will get the time complexity of this program as golden ration raised to the power n which is equal to O(1.6180)^n.

[HarryDulaney]

Exercise 18.02 says:
"*18.2 (Fibonacci numbers) Rewrite the fib method in Listing 18.2 using iterations."

The purpose of this exercise is actually to use a traditional iterative or looping approach to solving fibinanci numbers.
*The goal is not to write the fastest or most optimized algorithm, but to teach the utility of recursion by contrast with iteration.

closing this as it is not actually an issue*