Write a LEX program to check a Date of format (DD/MM/YYYY).

Code:

%{

#include<stdio.h>

int valid=0;

%}

%%

([0-2][0-9]|3[0-1])\/(0[1-9]|1[0-2])\/([1-2][0-9][0-9][0-9]) {valid=1;}

%%

main()

{

yyin=fopen("input.txt","r");

yylex();

if(valid==1) printf("It is a valid date\n");

else printf("It is not a valid date\n");

}

int yywrap()

{

return 1;

}