An american flag sort is an efficient, in-place variant of radix sort that distributes items into hundreds of buckets. Non-comparative sorting algorithms such as radix sort and american flag sort are typically used to sort large objects such as strings, for which comparison is not a unit-time operation.
American flag sort iterates through the bits of the objects, considering several bits of each object at a time. For each set of bits, american flag sort makes two passes through the array of objects: first to count the number of objects that will fall in each bin, and second to place each object in its bucket. This works especially well when sorting a byte at a time, using 256 buckets. With some optimizations, it is twice as fast as quicksort for large sets of strings.
The name comes by analogy with the Dutch national flag problem in the last step: efficiently partition the array into many "stripes".
Read more about American Flag Sort: Algorithm, Sample Implementation in Python
Famous quotes containing the words american, flag and/or sort:
“The American who has been confined, in his own country, to the sight of buildings designed after foreign models, is surprised on entering York Minster or St. Peter’s at Rome, by the feeling that these structures are imitations also,—faint copies of an invisible archetype.”
—Ralph Waldo Emerson (1803–1882)
“My dream is that as the years go by and the world knows more and more of America, it ... will turn to America for those moral inspirations that lie at the basis of all freedom ... that America will come into the full light of the day when all shall know that she puts human rights above all other rights, and that her flag is the flag not only of America but of humanity.”
—Woodrow Wilson (1856–1924)
“Why should I seek for love or study it?
It is of God and passes human wit;
I study hatred with great diligence,
For that’s a passion in my own control,
A sort of besom that can clear the soul
Of everything that is not mind or sense.”
—William Butler Yeats (1865–1939)