( ).

-1
-1
-2
-2
-3
-3
-4
-4
-5
-5
-6
-6
-7
-7
-8
-8
-9
-9
-10
-10
-11
-11
-12
-12
-13
-13
-14
-14
-15
-15
-16
-16
-17
-17
-18
-18
-19
-19
-20
-20
-21
-21
-22
-22
-23
-23