addr:       addr: +---------+               
                              |    0    |               
            +---------+       +---------+                                      
            | address |       | address |                
            +---------+       +---------+                
            | value   |       | value   |                
            +---------+       +---------+                
            | address |       | address |                
            +---------+       +---------+                
            | value   |       | value   |                
            +---------+       +---------+                
                 .                .                      
                 .                .                      
                 .                .                     
            +---------+       +---------+               
            | address |       | address |               
            +---------+       +---------+               
            | value   |       | value   |               
            +---------+       +---------+               
            |   0     |       |   0     |               
            +---------+       +---------+