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The selection sort algorithm sorts by finding the smallest element of an array, then the next smallest element, and so forth, using Theta(n) time at each step where n is the number of elements remaining. It is and example of a DecreaseByConstant algorithm and runs in Theta(n2) in both the worst and the best case.

Like InsertionSort, selection sort can be implemented in-place, with the output array appearing as a prefix of the input array:



Selection sort is more complicated than InsertionSort, has a slightly larger constant, is no faster asymptotically in the worst case, and is slower in the best case. InsertionSort is almost always a better choice.


2014-06-17 11:58