Count the number of signed numbers using Flex [ lex program part 8 ]

1.How to install Flex for linux ( lexical analyser generators) lex part 1 2.Replace space with $ [ lex program part 2 ] 3. Count the number of lines [lex program part3 ] 4.Count the number of digits [ lex program part 4 ] 5.Accept a string ending with abb [ lex program part 5 ] 6.Remove white spaces from a string using Flex [ lex program part 6 ] 7.Even number of 1's using Flex [ lex program part 7 ] 8.Count the number of signed numbers using Flex [ lex program part 8 ] 9.Count the nuber of Sentences and Words using Flex [ lex program part 9 ]

PROGRAM

       

%{
int c=0;
%}
str [-|+][0-9]*
%%

{str} c++;

%%

void main()
{
int b;
printf("Enter a the number \n");
yylex();
printf("number of signed numbers are %d \n",c);

}
        
    

OUTPUT

   

lex cns.l
cc lex.yy.c -lfl
./a.out
        
    

 then press CTRL+d

Posted in: Lex tutorial