Hi Guys,
I am trying to build a Parse Tree with the following grammar. I have
implemented my insertions using a standard binary tree inserting algorithm.
With the psuedocode below, can you guys provide any helpful feedback to placing
insert statements into building nodes of the tree. Any suggestions on how to
build the tree will be appreciated.
I hope to build the tree to look like that
5+4
Goal
|
|
|
Expr
|
|
Term
|
Factor
|
|
+
/ \
5 4
eprime()
/*Expr' -> + Term Expr' */
/* Expr' -> - Term Expr'*/
if(word = t or word = -) then
word <-NextWord()
if(Term()=false)
then return false;
else return Eprime();
/*Expr' -> Empty Set */
return true;
Term()
/*Term -> Factor Term'*/
if(factor()=false)
then return false
else return Tprime()
Tprime ()
/* Term' -> x factor Term' */
/*Term' -> / factor Term'*/
if (word = x or word = / )
Word=NextWord()
if(factor () = false)
then return false;
then return TPrime();
/*Term' -> Empty Set */
return True;
Factor()
/*Factor -> (Expr) */
if(word = '(' ) then
word<-Nextword();
if(Expr()-> false)
then return false
else if (word != ')') then
return false;
/*Factor ->Num*/
/*Factor->ident*/
else if(word!= Num and word != ident) then
report syntax error
return false;
word <- Nextword()
return true;
Main()
/* goal-> Expr */
Word <-Nextword()
if(expr() and word=eof)
then proceed to the next step
else return false
Expr()
/*Expr -> Term Expr' */
if(Term ()= false)
then return false
else return Eprime()
[Non-text portions of this message have been removed]
