Add a method to judge if a graph is directed or undirected by its edges
Add Cartesian quadrants selection algorithms.
Update README
Cartesian quadrants selection: a bit faster bitwise algorithm
Merge pull request #56 from EvgenyKarkan/new

Add Cartesian quadrants selection algorithms.
Update README.md
Cartesian quadrant selection: add one more bitwise algorithm
Updated main.m
Merge branch 'master' of https://github.com/EvgenyKarkan/EKAlgorithms
Cartesian quadrant selection: use NS_INLINE and add link to detailed discussion
Cartesian quadrant selection: remove obsolete lines
Merge branch 'master' of https://github.com/EvgenyKarkan/EKAlgorithms
Quick Sort: add tests
Better -[NSArray hasDuplicates]
Merge pull request #57 from stanislaw/master

Quick Sort: add tests
Merge pull request #58 from EvgenyKarkan/new

Better -[NSArray hasDuplicates]
Merge remote-tracking branch 'upstream/master' into Development
Add AVL Tree Structure
Finish AVL Tree data structure with insert and delete operation