Should you eat the week-old pizza?

Should you eat the week-old pizza?

       Does it have furr?
               +  +
               |  |
               |  |
       Yes<----+  +---->No
        +               +
        |               |
        |               v
        |     Is it visibly mouldy?
        |            +   +
        |            |   v
        |       Yes<-+  No
        |        +       +
        v        v       |
  Don't eat the pizza    |
                         v
                     Eat the pizza
                         +
                         |
                         |
               Yum<------+


-.,n