其余元素组成的表
() 原子(单元素)是结构上不可再分的可以是一个数或一个结构而表带结构本质就是广义表因作为广义表的元素故称为子表()大写字母 ()小写字母 ()表中元素的个数()表展开后所含括号的层数
深度
()() ()(()) () ()
head(head(tail(tail(head(tail(tail(A)))))))
表展开后所含括号的层数
() ()
head(head(tail(LS)))
head(tail(tail(head(tail(head(A))))))
[] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] [] []