Q:

Getting values from cells in table using class.  Jquery

How can I get values from cells in table using class? 
Col2, Col3, Col4 have common class "punkty".  In Col5 I want set result of addition from Col2,Col3,Col4.  In my recent solve, I'm getting string values from row, example "13230", by I would getting 13 and 23 and 0, then input value 36 to Col5. 
$("#tab tr").each(function (idx) {
  var ar = $(this).find('.punkty').text();
  alert(ar);
}

JSFiddle
Anybody can help me? :) 

A:

Try this:-
Fiddle
You can use the text attributes function to calculate the sum from siblings and set its own text. 
 $('#tab tr .suma').text(function(){
   var sum = 0; 
    $(this).siblings('.punkty').each(function(){ //Iterate through the siblings to calculate the sum. 
     sum += +$(this).text();
    })
 return (sum==0 ? '-' :  sum) ; //return '-' if no sum. 
});

