Merge k sorted arrays

http://www.geeksforgeeks.org/merge-k-sorted-arrays/

http://algorithms.tutorialhorizon.com/merge-k-sorted-arrays/

http://www.programcreek.com/2014/05/merge-k-sorted-arrays-in-java/
http://www.programcreek.com/2013/02/leetcode-merge-k-sorted-lists-java/