%{

#include "head.h"

#include "y.tab.h"

#include<iostream>

#include<string>

using namespace std;

extern YYSTYPE yylval;

%}

digit [0-9]

letter [A-Za-z]

word {letter}({letter}|{digit})*

whitespace ([ \t]*)

compare [<>=]|(!=)|(>=)|(<=)|(like)

number {digit}+\.?(digit)*

%%

[\(] {return LEFTPARENTHESIS;}

[\)] {return RIGHTPARENTHESIS;}

select {return SELECT;}

from {return FROM;}

where {return WHERE;}

{whitespace} {}

and {yylval = new TreeNode("AND"); return LOGIC;}

or {yylval = new TreeNode("OR"); return LOGIC;}

, {return COMMA;}

; {return SEMICOLON;}

{compare} {yylval = new TreeNode(yytext);return COMPARE;}

{number} {yylval = new TreeNode(yytext); return NUMBER;}

{word} {yylval = new TreeNode(yytext); return WORD;}

. {}

%%

int yywrap(void) {

return 1;

}

int yyerror(string s)

{

cout << s << endl;

return 1;

}