一、 1. F 2. T 二、 1. A 2. A 3. B 三 1.

(1)

一、

1. F 2. T

二、

1. A 2. A 3. B

三 1.

b

b b

b a

a

0 1 2 3

2.

(a) declaration  type var-list

type  int | float

var-list  identifier ID ID  , var-list | ε

(b)

FIRST(declaration) = { int, float } FOLLOW(declaration) = { $ } FIRST(type) = { int, float} FOLLOW(type) = { identifier } FIRST(var-list) = { identifier } FOLLOW(var-list) = { $ } FIRST(ID) = { , , ε} FOLLOW(ID) = { $ }

(2)

(c)

int float , identifier $

declaration

 type var-list

declaration  type var-list type type  int type  float

var-list var-list 

identifier ID

ID ID  ,

var-list ID  ε

(d)

Parsing Input Action

$declaration int x, y, z$ declaration  type var-list

$var-list type int x, y, z$ type  int

$var-list int int x, y, z$ match

$var-list x, y, z$ var-list  identifier ID

$ID identifier x, y, z$ match

$ID , y, z$ ID  , var-list

$var-list , , y, z$ match

$var-list y, z$ var-list  identifier ID

$ID identifier y, z$ match

$ID , z$ ID  , var-list

$var-list , , z$ match

$var-list z$ var-list  identifier ID

$ID identifier z$ match

$ID $ ID ε

$ $ accept