=begin

A Pythagorean triplet is a set of three natural numbers, abc, for which,
  a² + b² = c²

  For example, 3² + 4² = 9 + 16 = 25 = 5².

  There exists exactly one Pythagorean triplet for which a + b + c = 1000.
  Find the product abc.

=end

1.upto 1000 do |c|
  1.upto c do |b|
    1.upto b do |a|
      if a+b+c == 1000
        if a**2 + b**2 == c**2
          print(a.to_s+'x'+b.to_s+'x'+c.to_s+'='+(a*b*c).to_s)
          exit
        end
      end
    end
  end
end