Revert "Merge pull request #69 from takano32/K-knows-every-thing" $B$R$I$$(B
Revert "Merge pull request #69 from takano32/K-knows-every-thing"
$B$R$I$$(B

This reverts commit ab0fdea6be18d5e2f6f4fe4c54d2f4262795cbda, reversing
changes made to 537c06402d926f9b355468829d3c919364e14ecb.

tinbotu/sub,tinbotu/sub