Arne Andersson and Stefan Nilsson. A new efficient radix sort.
In Proc. 35th Annual IEEE Symposium on Foundations of Computer Science, pages 714--721. IEEE Computer Society Press, 1994.

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We present new improved algorithms for the sorting problem. The algorithms are not only efficient but also clear and simple. First, we introduce Forward Radix Sort which combines the advantages of tr aditional left-to-right and right-to-left radix sort in a simple manner. We argue that this algorithm will work very well in practice. Adding a preprocessing step, we obtain an algorithm with attractive theoretical properties. For example, n binary strings can be sorted in Theta (n log(B/(n log n)+2)) time, where B is the minimum number of bits that have to be inspected to distinguish the strings. This is an improvement over the previously best known result by Paige and Tarjan. The complexity may also be expressed in terms of H, the entropy of the input: n strings from a stationary ergodic process can be sorted in Theta (n log (1/H+1)) time, an improvement over the result recently presented by Chen and Reif.

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