How many movies have Ruggero Mastroianni and Valentino Macchi collaborated on?

They have worked on 6 movies together! Their first movie together was Shoot Loud, Louder... I Don't Understand (1966) while their highest rated movie together was Conversation Piece (1974). They have not worked together since Diary of a Maniac (1993). They are most known for their drama films together.