Logsort

Logsort is an O(n log n) stable quick sort using only O(log n) extra space. It uses a novel yet simple partitioning technique to reduce the amount of space needed for a stable partition from O(n) to O(log n). However, like O(n) in-place merging, Logsort's partition performs much more data moves and is more complicated than a regular O(n) space partition.