#!/usr/bin/env ruby
#-*- coding: utf-8 -*-

hankei=100
sousu=20000
kaisu=0


i = sousu

while i > 0

  x = Random.rand * hankei
  y =  Random.rand * hankei
  printf("x%f2  y%f1\n",x,y)
  printf("%f\n",y)
  
  if x * x + y * y  <= hankei * hankei  
      kaisu = kaisu + 1
  end

                                       
  
 i = i - 1
end
printf("kaisu %d\n",kaisu)
pai = 4.0 * kaisu.to_i / sousu.to_i

printf("pai = %f",pai)