- #!/usr/bin/env ruby
- require 'prime'
- require 'mathn'
- def shifts(arr)
- res = []
- tmp = arr.dup
- (0..arr.length-1).each do |a|
- tmp << tmp.shift
- res << tmp.dup
- end
- res
- end
- no_zeros = Prime.each(1000000).select do |num|
- ! num.to_s.split("").include?("0")
- end
- res = no_zeros.select do |num|
- shifts(num.to_s.split("")).all? do |n|
- n.join.to_i.prime?
- end
- end
- p res.size