/*** Definition Section ***/
%{
int v=0;
int k=0;
int t=0;
%}

/*** Rule Section ***/
%%
^if|else|while|int|switch|for|char t++ ; printf("Valid Keywords\n");
^[_]*[a-zA-Z][a-zA-Z0-9]*[_]* v++ ; printf("Valid Identifier\n");
^([//]*[/*]*)[0-9]*[A-Z]*([//]*[/*]*)+ v++; printf("Valid Identifier\n");
^[/]+[a-zA-z]*[0-9]*[/]+ k++; printf("Valid Comments\n");

\n {return 0;}
%%

/*** Code Section ***/
int yywrap(){}
int main(){
yylex();
if (v==0 && k==0 && t==0) printf("Invalid \n");
return 0;
}