Use Benchmark to test Fibonacci Sequence Using Iteration and Recursion

fibonacci.rb

# use iteration 
def iterative_fib(n)
  fib = [1, 1]
  a = 0
  b = 1

  n.times do
    fib << fib[a] + fib[b]
    a += 1
    b += 1
  end

  return fib[n]
end

# use recursion 
def recursive_fib(n)
  if n == 0 
    return 0
  elsif n == 1
    return 1 
  else 
    return recursive_fib(n-1) + recursive_fib(n-2)
  end
end

# Benchmark
require 'benchmark'
num = 35
Benchmark.bm do |x|
  x.report("recursive_fib") { recursive_fib(num) }
  x.report("iterative_fib")  { iterative_fib(num)  }
end