Collections
PV178: Programming for .NET Framework
CLI Libraries, Base Class Library (seminar)
Vojtˇech Forejt, forejt@fi.muni.cz
Martin Osovsk´y, osovsky@ics.muni.cz
Faculty of Informatics and Institute of Computer Science
Masaryk University
February 26, 2009
Collections
Motivation ­ "Sparse List"
List in which many items are missing (i.e. have default value).
Memory-saving implementation is desirable.
Collections
Sparse List
Download and open SparseListExample.zip from IS
SparseList<T> implements IList<T>
How it works:
variable count denotes real size of the list.
Two arrayslists: indices and values. Non-default item item
is at position k in the sparse list iff then for some n we have
indices[n]=k and values[n]=item.
numbers in indices are sorted incrementally.
E.g. for sparse list of integers: count=6, indices={1,3} and
values={9,8} determine list {0,9,0,8,0,0}.
Collections
Sparse Lists ­ Assignment
1 Implement the things that are missing (to find out which
ones, try to build the project)
2 Implement static method
WriteToFile<T>(SparseList<T>,string) in Program.
The method should output elements of the list to the file
given by string, each element at one line.
Collections
Homework
Will be available in IS by tomorrow morning
Topic: Enumerators, Streams, Filesystem
Deadline: March 15, 2009