On Computing the Degree of Convexity of Polyominoes
نویسندگان
چکیده
In this paper we present an algorithm which has as input a convex polyomino P and computes its degree of convexity, defined as the smallest integer k such that any two cells of P can be joined by a monotone path inside P with at most k changes of direction. The algorithm uses space O(m + n) to represent a polyomino P with n rows andm columns, and has time complexity O(min(m, rk)), where r is the number of corners of P . Moreover, the algorithm leads naturally to a decomposition of P into simpler polyominoes.
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ورودعنوان ژورنال:
- Electr. J. Comb.
دوره 22 شماره
صفحات -
تاریخ انتشار 2015