require 'benchmark'

N = 1000
BASIC_LENGTH = 10

puts RUBY_DESCRIPTION

5.times do |factor|
  length = BASIC_LENGTH * (10 ** factor)
  puts "_" * 60 + "\nLENGTH: #{length}"

  Benchmark.bm(10, '+= VS <<', '#{} VS <<') do |x|
    concat_report = x.report("+=")  do
      str1 = ""
      str2 = "s" * length
      N.times { str1 += str2 }
    end

    modify_report = x.report("<<")  do
      str1 = "s"
      str2 = "s" * length
      N.times { str1 << str2 }
    end

    interpolate_report = x.report('#{}')  do
      str1 = "s"
      str2 = "s" * length
      N.times { str1 = "#{str1}#{str2}" }
    end

    [concat_report / modify_report, interpolate_report / modify_report]
  end
end