text: #!/usr/bin/python
  
  from sys import *
  
  def number(s):
      if s.isdigit():
          return int(s)
      return float(s)
  
  if len(argv) != 3:
      print "usage: plot_distribution.py <min_value> <max_value>"
      exit(1)
  
  min_value = number(argv[1])
  max_value = number(argv[2])
  length = max_value - min_value
  
  print min_value, max_value
  groups = 20
  
  stat = [0] * groups
  
  for l in stdin:
      x = number(l.strip())
      stat[min(int(groups * (x - min_value) / length), groups - 1)] += 1
  
  for i in xrange(groups):
      left = min_value + i * length / groups
      right = min_value + (i + 1) * length / groups
      middle = (left + right) / 2
      print left, middle, right, stat[i]
  