%{
extern int lineno;
%}

%token PLUS SUB MULT DIV NUMBER LINE ERROR
%left PLUS SUB
%left MULT DIV
%%
S: E LINE { printf("Result= %d\n",$1);}
;
E: E PLUS T { $$=$1+$3;}
 | E SUB T { $$=$1-$3;}
 |T     {$$ = $1;}
;
T: T MULT F     { $$=$1*$3;}
 | T DIV  F  { $$=$1/$3; printf("Value=%d\n",$$);}
|F      {$$=$1;}
;
F: NUMBER  { $$=$1;}
;
%%
#include "lex.yy.c"
int yyerror()
{
        printf("Error at line no: %d\n",lineno);
}
int main()
{
printf("Enter the Expression: ");
yyparse();
return 0;
}