选择合适的存储结构表示广义表

(1)用大写字母表示广义表，用小写字母表示原子，并提供设置广义表的值的功能。

(2)取广义表L的表头和表尾的函数head(L)和tail(L)。

(3)能用这两个函数的复合形式求出广义表中的指定元素。

(4)由广义表的字符串形式到广义表的转换函数Str．To-Lists(S)：Lists，例如Str．To-Lists(’(a，(a，b)，c)’)的值为一个广义表。

(5)由广义表到广义表的字符串形式的转换函数Lists-To-Str(L)：String。

(6)最好能设置多个广义表。

-Select the appropriate storage structure represents generalized table

(1) capital letters generalized table showing atomic lowercase letters, and provide the settings generalized list of features values.

(2) to take generalized table table header and function L head (L) and tail (L) of the tail.

(3) the composite form of these two functions can be determined　the generalized elements specified in the table.

(4) by the string table to form generalized conversion function Str generalized list. To-Lists (S): Lists, such as Str. To-Lists ( (a, (a, b), c) ) of the value of a generalized form.

(5) by a generalized table to generalized list of string conversion functions Lists-To-Str (L): String.

(6) it is best to set up multiple generalized table.