with your code the reason might be because your code looks very similar to mine week ago 
if one wanted to, they could easily plug peaces of my code into yours and make it shorter with just copy/replace.
after some 230 I got bored enough to totally take down the loop construct and finally ended up the monster I had. but for starting code, yours look way much like mine.
in my original code (376) I even had this:
$a=$a+$x[($b & 128)>0]+$x[($b & 64)>0]+$x[($b & 32)>0]+$x[($b & 16)>0]+$x[($b & 8)>0]+$x[($b & 4)>0]+$x[($b & 2)>0]+$x[($b & 1)>0]
don't remember any more was it because I wanted to make my code long or what 
anyways, I am sad that some of you guys didn't/don't have time to really compete in this round. maybe next time then.
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!download
KiXnet
