Brian teaser: use 6 matchsticks to build 4 equilaterral triangles?
thanks.
来源: LordSeth 于 08-08-19 10:37:17
http://web.wenxuecity.com/BBSView.php?SubID=mysj&MsgID=27364
thanks.
来源: LordSeth 于 08-08-19 10:37:17
http://web.wenxuecity.com/BBSView.php?SubID=mysj&MsgID=27364