What wrong with my IDEA? : I cant understand whats wrong with my IDEA. In this code i getting errors like this when im trying to assign a value to a variable within a class. Also System.out.println doesnt work in this classes:
1.Identifier expected
2.Unexpected token
3.Unknown class "windows"


    public static void main(String[] args) {

    }

    class building{
        int apart_num;
        apart_num = 3;
    }

    class apartments{
        double area;
        int lightbulb;
        int windows;
        windows = 4;
    }

    interface construct_building{

    }

    interface construct_apartments{

    }

