,---------------------------------.                       
                       |User                             |                       
                       |---------------------------------|                       
                       |+id: int                         |                       
                       |+name: String                    |                       
                       |                                 |                       
                       |- writeArticle(content: string)  |                       
                       |- commentArticle(content: string)|                       
                       `---------------------------------'                       
                                         |                                       
                                         |                                       
,-----------------.  ,-------------------------------------.   ,----------------.
|Article          |  |Admin                                |   |Comment         |
|-----------------|  |-------------------------------------|   |----------------|
|+ id: int        |  |- deleteArticle(id: int)             |   |+id: int        |
|+ author: int    |  |- deleteComment(id: int)             |   |+content: string|
|+ content: string|  |- editArticle(id: int, content: int) |   |+author: int    |
`-----------------'  |- editComment(id: int, content: int) |   `----------------'
                     `-------------------------------------'                     
                                                                                 
                                    ,--------.                                   
                                    |Visitor |                                   
                                    |--------|                                   
                                    |browse()|                                   
                                    `--------'