Improved randomized selection
نویسنده
چکیده
We show that several versions of Floyd and Rivest’s improved algorithm Select for finding the kth smallest of n elements require at most n + min{k, n − k} + O(n1/2 ln n) comparisons on average and with high probability. This rectifies the analysis of Floyd and Rivest, and extends it to the case of nondistinct elements. Encouraging computational results on large median-finding problems are reported.
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ورودعنوان ژورنال:
- CoRR
دوره cs.DS/0402005 شماره
صفحات -
تاریخ انتشار 2004