What did the warren commission conclude about the number of killer?

The highly flawed Warren Commission to investigate the assassination of US President Kennedy concluded that there was one shooter. That person was Lee Harvey Oswald. One quick comment on this: Imagine a person bent on assassinating the US President. Now imagine the odds of the President's travel route passing right next to where you work. Imagine you also had an ancient Italian carbine. Imagine that time after time FBI and/or military snipers unable to duplicate the "assassination" and failing.