xiaobendan158.blog.163.com/blog/static/79231334201310292158405/
avercheva.ru
, , 2 3 .
-
- (- , - )
- ( -, )
( 2- 1- , .)
2
( , 2- )
2 .
4 ( 2- . , 2 , 2- . )
4 (2 . , 2- , 2 . )