bench.rb

# step 1 - eval apple*x and assign to long_string
long_string = "apple"*100000000

# step 2 - define method benchmark
def benchmark
  before = Time.now.to_i
  yield # step 4 - evaluate the block
  Time.now.to_i - before # step 5 - return the time
end

# step 3 - call benchmark with a block
running_time = benchmark { long_string.reverse } # step 6 - assign value to running_time

puts running_time