($N,$K)=<>;
map{
	$a=0;
	$a+=0|4+rand 3for 1..$K;
	$a+=0|1+rand 6for$K+1..$N;
	$a-=0|1+rand 6for 1..$N;
	$%+=$a>0;
}1..7e5;
print$%/7e5