This is the Euclidean algorithm for finding the Greatest common divisor between two numbers. I thought I'd throw a bit of my own code into the fray. The first one uses a loop, the second uses recursion. Could someone benchmark this for me? 
#!/usr/bin/perl -w


print "GCD: " . GCD( 45, 5 ) . " RecGCD: " . RecGCD( 45, 5 ) . "\n";

#Assumes $A is the largest number
sub GCD 
{
    $A = shift;
    $B = shift;
    $R = 1;
    
    while ( $R != 0 )
    {
        $R = $A % $B;
        
        if ( $R == 0 )
        {
            return $B;
        }
        
        $A = $B;
        $B = $R;
    }
}


#Assumes $A is the largest number
sub RecGCD
{
    $A = shift;
    $B = shift;
    $R = 0;
    
    $R = $A % $B;
    
    if ( $R == 0 )
    {
        return $B;
    }
    
    RecGCD( $B, $R );    
}

[download]


--=Lolindrath=--

In reply to Re: Recursion: An example of Looping and Recursion by lolindrath
in thread Recursion by lolindrath

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