i need to do alogic circuit that do the following
when i input anumber it count hoe many ones are there
for example:

0101 conts 010 means 2
and i want you to provide me with gates need and number of the component and if possible adraw of the circuit needed

 

What you are looking for is called a "parity checker." Google it, and see http://www.alldatasheet.com/view.jsp?Searchword=M74HC280.

I would guess that English is not your native language. In English, "I want" comes across as a demand, and will greatly reduce the number of responses you get. "I would like" is a better form.

--Rich