A Lex Program to detect errors in a C/C++ program

lexical_analyzer.lex

%{ 
int n = 0, limit = 0, cursor = 0; 
char identifiers[100][100];
int identify = 0;
%} 

%% 

"while"|"if"|"else"|"for" {n++;printf("\t keywords : %s\n", yytext);} 

"int"|"float" {n++;printf("\t keywords : %s\t", yytext); 
	if(strcmp(yytext, "int") == 0) {
		identify = 1;
	} else if(strcmp(yytext, "float") == 0) {
		
		identify = 1;
	}
}

[a-zA-Z_][a-zA-Z0-9_]* { 
if(identify) {
	printf("\t identifier : %s\n", yytext);
	strcpy(identifiers[limit], yytext);
} else {
	int k = 0;
	for(int i = 0; i <= limit; i++) {
		if(strcmp(identifiers[i], yytext) == 0) {
			printf("\t identifier: %s\n", yytext);
			k = 1;
			break;
		}
	}
	if(k == 0) {
			printf("\t Unrecognized Token: %s\n", yytext);	
			return 0;
		}
} };  

"<="|"=="|"="|"++"|"-"|"*"|"+" {n++;printf("\t operator : %s\n", yytext);} 

[(){}|,;] {n++;printf("\t separator : %s\n", yytext); 
if(strcmp(yytext, ";")== 0){
identify = 0;
limit++;
}
if(strcmp(yytext, ",") == 0) {
	limit++;
}
}  

[0-9]*"."[0-9]+ {n++;printf("\t float : %s\n", yytext);} 

[0-9]+ {n++;printf("\t integer : %s\n", yytext);}						 

%% 


int main() 

{ 
	yylex(); 
	printf("\n total no. of token = %d\n", n); 
	return 0;
}