Definition: A sort algorithm that splits the items to be sorted into two groups, recursively sorts each group, and merges them into a final, sorted sequence. Run time is Θ(n log n).
Generalization (I am a kind of ...)
Specialization (... is a kind of me.)
k-way merge sort, balanced k-way merge sort, polyphase merge sort.
Aggregate child (... is a part of or used in me.)
divide and conquer.
See also external sort, bitonic sort, strand sort.
Note: There seem to be some references to linear-time in-place merging; look for papers by Geffert, Katajainen & Pasanen.
animation (Java). Comparison of quicksort, heapsort, and merge sort on modern processors.
If you have suggestions, corrections, or comments, please get in touch with Paul E. Black.
Entry modified 24 August 2009.
HTML page formatted Tue Dec 6 16:16:32 2011.
Cite this as:
Paul E. Black, "merge sort", in Dictionary of Algorithms and Data Structures [online], Paul E. Black, ed., U.S. National Institute of Standards and Technology. 24 August 2009. (accessed TODAY) Available from: http://www.nist.gov/dads/HTML/mergesort.html