Alphabetic Minimax Trees in Linear Time
نویسنده
چکیده
We develop a linear time algorithm algorithm for the following problem: given an ordered sequence of n real weights w1, w2, . . . , wn, construct a binary tree on n leaves labeled with those weights when read from left to right so that the maximum value of wi plus depth of the i-th leftmost leaf is minimized. This improves the previously known O(n logn) time solutions [2,11,13]. We also give a simplified O(nd) version of the algorithm, where d is the number of distinct integer parts of wi, which does not require the full power of the word RAM model. This improves the previously known O(nd log log n) solution of Gagie [5]. Key-words: minimax tree, Yeung’s inequality, word RAM
منابع مشابه
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تاریخ انتشار 2013