Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Label Placement in Road Maps   A road map can be interpreted as a graph embedded in the plane, in which each
vertex corresponds to a road junction and each edge to a particular road
section. We consider the cartographic problem to place non-overlapping road
labels along the edges so that as many road sections as possible are identified
by their name, i.e., covered by a label. We show that this is NP-hard in
general, but the problem can be solved in polynomial time if the road map is an
embedded tree.

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The categories of this paper are: dg-ga
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The categories of this paper are: eess
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: bayes-an
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The categories of this paper are: physics
4
The categories of this paper are: cond-mat
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph