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# Licensed under the Apache License, Version 2.0 (the "License"). You
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import dwave_networkx as dnx
import networkx as nx
from dwave.system.composites import EmbeddingComposite

from braket.ocean_plugin import BraketSampler

# Use a default online D-Wave device ARN
sampler = BraketSampler()
print("Using device ARN", sampler.solver.arn)

star_graph = nx.star_graph(4)  # star graph where node 0 is connected to 4 other nodes

# EmbeddingComposite automatically maps the problem to the structure of the solver.
embedded_sampler = EmbeddingComposite(sampler)

# The below result should be 0 because node 0 is connected to the 4 other nodes in a star graph
print(dnx.min_vertex_cover(star_graph, embedded_sampler, resultFormat="HISTOGRAM"))