Four different Ruby examples creating the Fibonacci sequence and calculating time consuming.

fibonacci.rb

require 'timify'

num=36

t=Timify.new :count, show:false

## Example 1
t.add
f = lambda { |x| x < 2 ? x : f.call(x-1) + f.call(x-2) }
puts f.call(num)
t.add :example1

## Example 2
f = ->(x){ x < 2 ? x : f[x-1] + f[x-2] }
puts f[num]
t.add :example2

## Example 3
def fibonacci( n )
  return  n  if ( 0..1 ).include? n
  ( fibonacci( n - 1 ) + fibonacci( n - 2 ) )
end
puts fibonacci(num)
t.add :example3


## Example 4
def fib(n)
  n < 2 ? n : fib(n-1) + fib(n-2)
end
puts fib(num)
t.add :example4

## Print time consumed by different examples
pp t.totals[:labels]