Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: BitPath -- Label Order Constrained Reachability Queries over Large
  Graphs   In this paper we focus on the following constrained reachability problem over
edge-labeled graphs like RDF -- "given source node x, destination node y, and a
sequence of edge labels (a, b, c, d), is there a path between the two nodes
such that the edge labels on the path satisfy a regular expression
"*a.*b.*c.*d.*". A "*" before "a" allows any other edge label to appear on the
path before edge "a". "a.*" forces at least one edge with label "a". ".*" after
"a" allows zero or more edge labels after "a" and before "b". Our query
processing algorithm uses simple divide-and-conquer and greedy pruning
procedures to limit the search space. However, our graph indexing technique --
based on "compressed bit-vectors" -- allows indexing large graphs which
otherwise would have been infeasible. We have evaluated our approach on graphs
with more than 22 million edges and 6 million nodes -- much larger compared to
the datasets used in the contemporary work on path queries.

21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga