-  "N" ()
- "N" () "P" ()

      -  "D" (1-
- "D" (1- )

      -  "D" (2-
- "D" (2- )

      -  "D" (3-
- "D" (3- )

      -  "D" (4-
- "D" (4- )

      -  "R" (
- "R" ( )

      -
      (, , ) , ...


      . . . 20 ...


      , : 1. , ...