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A combinatorial theorem on labeling squares with points and its application. (English) Zbl 1137.05050

Summary: We present a combinatorial theorem on labeling disjoint axis-parallel squares of edge length two using points. Given an arbitrary set of disjoint axis-parallel squares of edge length two, we show that if we label points on the boundary of all squares (one for each square) and define a distance label graph such that there is an edge between any two labeling points if and only if their \(L_\infty\)-distance is at most \(1-\varepsilon\) (\(0 < \varepsilon < 1\)), then the maximum connected component of the graph contains \(\Theta(1/\varepsilon)\) vertices, which is tight. With this theorem we present a new and simple factor-\((3 + \varepsilon)\) approximation for labeling points with axis-parallel squares under the slider model.

MSC:

05C62 Graph representations (geometric and intersection representations, etc.)
05C90 Applications of graph theory
90C27 Combinatorial optimization
Full Text: DOI

References:

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