Maps/ADT

Map Abstract Data Type

The map abstract data type must support the following basic operations:

• m[k] or m.get(k) - get the value v associated with key k in map m, returns key error
• m[k] = v or m.set(k,v) or m.put(k,v) - set the value v associated with key k in map m
• del m[k] or m.remove(k) - remove the element with key k in map m
• len(m) or m.size() - return the number of elements (unique keys) in the map
• iter(m) - iterator over keys of map

Other convenience methods:

• m.contains(k) or k in m - perform search to see if map m contains key k
• m.get(k, d=None) - return m[k] if key k exists in the map, otherwise return a default value in place of a key error
• m.setdefault(k,d) - if key k exists in map, return m[k]. otherwise, set m[k] to default value d and return value
• m.pop(k, d=None) - remove item associated with key k from map and return associated value v
• m.popItem() - remove arbitrary key-vlue pair from the map, and return a (k,v) tuple representing the removed pair. raise key error if empty map.
• m.clear() - remove key-value pairs from map
• m.keys() - return set-like view of keys
• m.value() - return set-like view of values
• m.items() - return set-like view of (k,v) tuples for entries of m
• m.update(m2) - assign m[k] = v for every (k,v) pair in map m2
• m.equals(m2) m.compareTo(m2) etc.

Java Variation

Basic operations:

• size()
• isEmpty()
• get(k)
• put(k,v)
• remove(k)
• keySet()
• values()
• entrySet()