From: Josef 'Jupp' SCHUGT <jupp@...>
Date: 2003-12-12T07:19:18+09:00
Subject: Re: prog for g.c.d. of 2 integers

Hi!

* Van Jacques; 2003-12-11, 14:14 UTC:
> Topics from mathematics make good practice programs, IMO.

I don't agree with that. When starting with mathematics the most
important task of programming has already taken place: The modelling
of the problem in an abstract way.

> Comments are welcome.

My implementations are these:

def Extmath.gcd(m, n)
  m = Integer(m)
  n = Integer(n)
  if m <= 0 || n <= 0
    return nil
  end
  loop {
    if m < n
      m, n = n, m
    end
    if (l = m % n) == 0
      break
    end
    m = l
  }
  n
end

def Extmath.lcm(m, n)
  m = Integer(m)
  n = Integer(n)
  if m <= 0 || n <= 0
    return nil
  end
  m / gcd(m, n) * n
end

They are part of extmath - http://extmath.rubyforge.org/

Josef 'Jupp' SCHUGT
-- 
http://oss.erdfunkstelle.de/ruby/    -    German comp.lang.ruby-FAQ
http://rubyforge.org/users/jupp/     -    Ruby projects at Rubyforge