$li ="abbjghfg table 1 vinoth figer table2";
 $f=$li;
  while($f=~m /table[ ]([0-9])+|table([0-9])+|fig[ ][0-9]+|fig[0-9]+/i)
  {
     $f = $';
    #print "  after ----$f \n ";

     $match_key=$&;
       #print " --match : --$match_key \n ";

     $front=$`;
     $rep=$front."<aid=".$match_key.$';
     print" $rep \n";

  }