1 z

     2 \c

     3 \c2

     4 C

     5 C2

     6 x

     7 x1

     8 x1z

     9 u

    10 uz

    11 u1

    12 u1z

    13 u12

    14 u12z

    15 u123

    16 u123z

    17 x{z

    18 x{1z

    19 x{1,z

    20 x{1,2z

    21 x{10000,20000z

    22 

    23 

    24 null

    25 ]

    26 {

    27 }

    28 z

    29 c

    30 null

    31 x

    32 x

    33 x

    34 u

    35 u

    36 u

    37 u

    38 u

    39 u

    40 u

    41 u

    42 null

    43 null

    44 B

    45 null