1、给出文法如下：

G[E]

E->T|E+T

T->F|T*F

F->i(E)

可以构造算符优先表如下：

　　+　　*　　(　　)　　i

+　　　　　　　　　　

*　　　　　　　　　　

(　　　　　　　　　　

)　　　　　　　　　　

i　　　　　　　　　　



2、计算机中表示上述优先关系，优先关系的机内存放方式有两种1）直接存放，2）为优先关系建立优先函数，这里由学生自己选择一种方式；

3、给出算符优先分析算法如下：

k:=1 S[k]:=‘#’

REPEAT

把下一个输入符号读进a中；

IF S[k]∈VT THEN j:=k ELSE j:=k-1

WHILE S[j] a DO

BEGIN

REPEAT

Q:=S[j]

IF S[j-1]∈VT THEN j:=j-1 ELSE j:=j-2

UNTIL S[j] Q

把S[j+1]…S[k]归约为某个N；

k:=j+1

S[k]:=N

END OF WHILE

IF S[j] a OR S[j] a THEN

BEGIN

k:=k+1 S[k]:=a

END

ELSE ERROR

UNTIL a=‘#’

4、根据给出算法，利用适当的数据结构实现算符优先分析程序；-1 gives grammar as follows: E [E] E-> T | E+ T　T-> F | T* F　F-> i (E)

Operator priority table can be constructed as follows:+* () i

+

*

(

)

i

2, the computer indicated above priority, preferential relations machine memory put in two ways 1) Direct storage, 2) as a priority relationship building priority function, here by the students themselves choose a way

3, gives the operator precedence analysis algorithm is as follows:

k: = 1　S [k]: =　#　

REPEAT read the next input symbol into a medium　IF S [k] ∈VT THEN j: = k ELSE j: = k-1　WHILE S [j] a DO BEGIN REPEAT Q: = S [j]　IF S [j-1] ∈VT THEN j: = j-1 ELSE j: = j-2 UNTIL S [j] Q to S [j+ 1] ... S [k] is about a normalization N　k: = j+1　S [k]: = N　END OF WHILE

IF S [j] a OR S [j] a THEN BEGIN k: = k+ 1　S [k]: = a END ELSE ERROR UNTIL a =　#

4, according to the given algorithm, using the appropriate data structure to achieve operator priority analysis program