euclid algorithm

1int Euclid(int a, int b)
2{
3    int r;
4    while(b != 0) 
5    {
6         r = a % b;
7         a = b; 
8         b = r; 
9    }
10    return a; 
11}

1function gcd(a, b)
2    if b = 0
3        return a
4    else
5        return gcd(b, a mod b)
6

1 function mcd($a,$b) {
2	while($b) list($a,$b)=array($b,$a%$b);
3	return $a;
4}

1def MCD(a,b):
2    while b != 0:
3        a, b = b, a % b
4    return a