A Space-Efficient Algorithm for Segment Intersection
نویسندگان
چکیده
We examine the space requirement for the classic linesegment intersection problem. Using so-called implicit data structures, we show how to make the standard sweep-line algorithm run in O((n+ k) log n) time with only O(log n) extra space, where n is the number of line segments and k is the number of intersections. If division is allowed and input can be destroyed, the algorithm can run in O((n + k) log n) time with O(1) extra space.
منابع مشابه
Line - segment intersection made in - place ✩ Jan Vahrenhold
We present a space-efficient algorithm for reporting all k intersections induced by a set of n line segments in the plane. Our algorithm is an in-place variant of Balaban’s algorithm and, in the worst case, runs in O(n log2 n+ k) time using O(1) extra words of memory in addition to the space used for the input to the algorithm. © 2006 Elsevier B.V. All rights reserved.
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