# -*- coding: euc-jp -*-
require 'prime'


def prime_array(k)
  q = Prime::Generator23.new
  primes = Array.new
  q.each{|x|
    if primes.length < k
      primes << x
    else
      break
    end
  }
  primes
end

n = 10 ** 7  # 素数の個数
x = srand() 
prime = prime_array(n)

x = rand(n)
y = rand(n)
while true
  if y != x
    break
  else
    y = rand(n)
  end
end

a = prime[x]
b = prime[y]
pp = a * b

printf("prime = %d\n", pp)
printf("(a, b) = (%d, %d)\n", a, b)
t0 = Time.now.to_f

for n in prime
  if pp % n == 0 
    printf("%d, %d\n", n, pp / n)
    break
  end
end 

t1 = Time.now.to_f
printf("かかった時間: %f [s]\n", t1 - t0)