A LOWER BOUND TO FINDING CONVEX HULLS bY
نویسنده
چکیده
Given a set S of n distinct points { (xi'Yi) 1 0 5 i < n] 9 the convex hull problem is to determine the vertices of the convex hull H(S) . All the known algorithms for solving this problem have a worst-case running time of cn log n or higher, and employ only quadratic tests, i.e., tests of the form f(XoYO ⌧19 Yl> l l l ☺ ⌧nBl Y, 1> : 0 with f being any polynomial of degree not exceeding 2 . In this paper, we show that any algorithm in the quadratic decision-tree model must make cn log n tests for some input.
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