AASHAY

%{
	#include<stdlib.h>
	#include<stdio.h>
	#include<string.h>

	struct sym
	{
		char sname [15];

	}s[20];

	int refer = 0;

	int insert(char *yytext)
	{	int i = 0 ;
		for(i = 0;i < 20; i++)
			if(strcmp(s[i].sname,yytext) == 0)
			{	printf("\n%s keyword already there",yytext);
				return 0;
			}

		strcpy(s[refer++].sname,yytext);
		return 1;
	}

	void display()
	{	int i = 0;
		for(i = 0 ; i<20; i++)
			printf("%s\n",s[i].sname);
	}

%}

%%
"#include"[ \t]*"<"|\"[ \t]*[^\n"][ \t]*">"|\" 	{ printf("\n #include found: %s",yytext); insert(yytext);}
"main" 						{ printf("\n Main starts: %s",yytext);insert(yytext);}
"(" 						{ printf("\n Parenthesis: %s",yytext);insert(yytext);}
")" 						{ printf("\n Parenthesis: %s",yytext);insert(yytext);}
[0-9] 						{ printf("\n Number: %s",yytext);insert(yytext);}
"int"|"float"|"char"|"double"			{ printf("\n Keyword: %s",yytext);insert(yytext);}
","						{ printf("\n Comma: %s",yytext);insert(yytext);}
";"						{ printf("\n Semicolon: %s",yytext);insert(yytext);}
"::"						{ printf("\n Scope resolution: %s",yytext);insert(yytext);}
"*"|"+"|"-"|"/"					{ printf("\n Operator: %s",yytext);insert(yytext);}
"}"						{ display();}
"//"[^\n]					{ printf("\n Single line Comment: %s",yytext);insert(yytext);}
"/*"						{ printf("\n Multi line Comment Starts: %s",yytext);insert(yytext);}
"*/"						{ printf("\n Single line Comment Ends: %s",yytext);insert(yytext);}
%%


main()
{
FILE *file;
file=fopen("code.c","r");
yyin=file;
yylex();
}