CodeMocha » algorithm http://codemocha.com Freshly ground code. Thoughts on software and algorithms by Chet Mancini Fri, 18 Sep 2009 15:22:50 +0000 http://wordpress.org/?v=2.8 en hourly 1 Euclidean Algorithm http://codemocha.com/2009/07/euclidean-algorithm/ http://codemocha.com/2009/07/euclidean-algorithm/#comments Sat, 04 Jul 2009 03:46:41 +0000 Chet http://codemocha.com/?p=9 One of my favorite algorithms is the simple, elegant Euclidean algorithm for finding the greatest common denominator of two numbers. In ML or another functional language it really is beautiful:

1
2
fun gcd(a, 0) = a
   | gcd(a, b) = gcd(b, a mod b);

Of course, the same can be done in Java iteratively:

1
2
3
4
5
6
7
8
9
public int gcd(int a, int b){
    int c;
    while (b>0){
        c = a;
        a = b;
        b = c%b;
    }
    return a;
}

Or recursively:

1
2
3
4
5
6
7
public int gcd(int a, int b){
    if(b==0){
        return a;
    }else{
        return gcd(b, a%b);
    }
}
]]> http://codemocha.com/2009/07/euclidean-algorithm/feed/ 0