A C++ implementation of Distributed Directed Minimum Spanning Tree

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how to use:
1. make
2. ./bin/MST data/test.in

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test data (i.e. data/test.in) format:
num_nodes num_edges
edge0_start_nodeID edge0_end_nodeID edge0_weight
edge1_start_nodeID edge1_end_nodeID edge1_weight
...
edge{num_edges-1}_start_nodeID edge{num_edges-1}_end_nodeID edge{num_edges-1}_weight
where num_nodes is the number of nodes in the graph, and num_edges is the number of edges
then following num_edges line each represents an edge
for edge i, edge{i}_start_nodeID is the ID of starting node of this edge, edge{i}_weight is the weight of this edge
attention that nodeID starts from 0

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output format:
for each test case, output contains 2 lines
the first line is the result produced by the simulation of the distributed algorithm
the second line is the result produced by the centralized algorithm