A couple small improvements: 
perl -E'@x=split//,"0335443554366887798866555766";$_+=<>;print;while($
+_!=4){split//,"99aabb87780";$_?do{$x=0;$x+=hex(pop)*!!$&+($1&&$x[$1]+
+7)+($2>1?$x[$2+18]+$x[$3]:$x[$2.$3])while s/(.??)(.?)(.)$//}:($x=4);s
+ay" is $x.";print$_=$x}say" is magic."'

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In reply to Re^2: Code Golf: Four is magic by Haarg
in thread Code Golf: Four is magic by deMize

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