On Sat, Mar 29, 2008 at 10:31 PM, Sampath Gadamsetty
<[EMAIL PROTECTED]> wrote:
> 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
Have you looked into using lex and yacc, aka flex and bison, which are
open source equivalents?
> 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]
>
>
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