asda

require 'benchmark'

def fib1(n)
  #return n<2 ? n : fib1(n-1)+fib1(n-2)
  if n<2 then return n
  else return  fib1(n-1)+fib1(n-2)
  end
end


def fib2(n)
  i=1
  j=0
  n.times {
    j=i+j
    i=j-i
  }
  return j
end


def fib3(n)
  i=1
  j=0
  k=0
  h=1
  while n>0
    if n%2!=0
      t=j*h
      j=i*h+j*k+t
      i=i*k+t
    end
    t=h*h
    h=2*k*h+t
    k=k*k+t
    n/=2
  end
  return j
end

Benchmark.bm (10){ |x|
x.report("fib1time: ") { fib1(35)}}
puts


Benchmark.bm (10){ |x|
x.report("fib1time: ") { fib1(35)}}
puts 

Benchmark.bm (10){ |x|
x.report("fib1time: ") { fib1(35)}}
puts

Benchmark.bm (10){ |y|
y.report("fib2time: ") { fib2(208000)}}
puts

Benchmark.bm (10){ |z|
z.report("fib3time: ") { fib3(4000000)}}