edges.txt This file describes an undirected graph with integer edge costs. It has the format
[number_of_nodes] [number_of_edges]
[one_node_of_edge_1] [other_node_of_edge_1] [edge_1_cost]
[one_node_of_edge_2] [other_node_of_edge_2] [edge_2_cost]
The code implements Prim's minimum spanning tree algorithm on this graph.