Dictionary as ADT

• Domain:
• a collection of pairs; each pair consists of a key, and some additional data
  
  
• Operations (typical):
• Create a table (initially empty)
• Insert a new key-data pair in the table; if a key-data pair with the same key is already there, update the data part of the pair
• Find the key-data pair in the table corresponding to a given key; return the data
• Delete the key-data pair corresponding to a given key
• Enumerate (traverse) all key-data pairs in the table