public void Copy_must_work()
{
Vertex<string> source = new Vertex<string>("s");
Vertex<string> target = new Vertex<string>("t");
FlowGraph<string> flowGraph = new FlowGraph<string>(source, target, new List<Vertex<string>>() { source, target });
flowGraph.AddVertex("a");
flowGraph.AddVertex("b");
flowGraph.AddEdge("s", "a", 5, 2);
flowGraph.AddEdge("s", "b", 8, 4);
flowGraph.AddEdge("a", "b", 3, 0);
flowGraph.AddEdge("a", "t", 4, 2);
flowGraph.AddEdge("b", "t", 6, 4);
FlowGraph<string> flowGraphCopy = flowGraph.Copy();
Assert.IsFalse(ReferenceEquals(flowGraph.Vertices, flowGraphCopy.Vertices));
Assert.IsFalse(ReferenceEquals(flowGraph.Edges, flowGraphCopy.Edges));
Assert.IsFalse(ReferenceEquals(flowGraph.Vertices[0], flowGraphCopy.Vertices[0]));
Assert.IsFalse(ReferenceEquals(flowGraph.Edges[0], flowGraphCopy.Edges[0]));
}