Version 5.0 The LEDA User Manual

p dictionary D.change inf(p dic item it, const I& i)
int D.size( ) returns the size of D.
returns D.del item(it) ∪ {〈k, i〉}, where k =
key(it).
Precondition: it ∈ D.
bool D.empty( ) returns true if D is empty, false otherwise.
4. Implementation
Persistent dictionaries are implemented by leaf oriented persistent red black trees. Operations
insert, lookup, del item, del take time O(log 2 n), key, inf, empty, size and change inf
take time O(1). The space requirement is O(1) for each update operation.