euler35.rb

   1 require 'ruby-prof'
   2 load 'primes.rb'
   3
   4 class Array
   5   def to_i
   6     self.map {|d| d.to_s}.join.to_i
   7   end
   8
   9   def to_r
  10     Rational(self[0].to_i, self[1].to_i)
  11   end
  12
  13   def all_rotations
  14     (0...self.length).map {|r| self.rotate(r)}
  15   end
  16 end
  17
  18 class Integer
  19   @@primes = Primes.instance
  20
  21   def prime?
  22     @@primes.include? self
  23   end
  24
  25   def pl
  26     @@primes.primes.length
  27   end
  28
  29   def circular_prime?
  30     self.to_digits.all_rotations.map {|n| n.to_i}.all? {|n| n.prime?} if self.prime?
  31   end
  32
  33   def to_digits
  34     self.to_s.split('').map {|d| d.to_i}
  35   end
  36 end
  37
  38
  39 (10**6).prime?
  40
  41 RubyProf.start
  42
  43 pl0 = 0.pl
  44 beginning_time = Time.now
  45 cps = (2..10**6).select {|n| n.circular_prime?}
  46 end_time = Time.now
  47 pl1 = 0.pl
  48 puts "Time elapsed #{(end_time - beginning_time)} seconds, going from #{pl0} to #{pl1} primes cached"
  49 puts cps.length
  50
  51 result = RubyProf.stop
  52
  53 printer = RubyProf::MultiPrinter.new(result)
  54 printer.print(:path => ".", :profile => "profile")
  55
  56