public void TriangularGrid()
{
var g = new TestGraph(Enumerable.Range(1, 10).ToArray())
{
{ 1, new[] { 2, 3 } },
{ 2, new[] { 3, 4, 5 } },
{ 3, new[] { 5, 6 } },
{ 4, new[] { 5, 7, 8 } },
{ 5, new[] { 6, 8, 9 } },
{ 6, new[] { 9, 10 } },
{ 7, new[] { 8 } },
{ 8, new[] { 9 } },
{ 9, new[] { 10 } },
{ 10 },
};
var spGraph = ShortestPathGraph.Build(g, edge => edge.Owner == -1, new[] { 1 });
spGraph.ShouldBeEquivalentTo(
new TestShortestPathGraph
{
{ 1, 0, new[] { 2, 3 } },
{ 2, 1, new[] { 4, 5 } },
{ 3, 1, new[] { 5, 6 }, new[] { 2 } },
{ 4, 2, new[] { 7, 8 } },
{ 5, 2, new[] { 8, 9 }, new[] { 4 } },
{ 6, 2, new[] { 9, 10 }, new[] { 5 } },
{ 7, 3 },
{ 8, 3, null, new[] { 7 } },
{ 9, 3, null, new[] { 8 } },
{ 10, 3, null, new[] { 9 } },
});
}
public void Simple()
{
var g = new TestGraph(1, 2, 3, 4)
{
{ 1, new[] { 2, 3 } },
{ 2, new[] { 3, 4 } },
{ 3, new[] { 4 } },
{ 4 }
};
var spGraph = ShortestPathGraph.Build(g, edge => edge.Owner == -1, new[] { 1 });
spGraph.ShouldBeEquivalentTo(
new TestShortestPathGraph
{
{ 1, 0, new[] { 2, 3 } },
{ 2, 1, new[] { 4 } },
{ 3, 1, new[] { 4 }, new[] { 2 } },
{ 4, 2 }
});
}
public static ShortestPathGraph Build(Graph graph, Func <Edge, bool> takeEdge, ICollection <int> sourceVertexes)
{
var spGraph = new ShortestPathGraph();
var queue = new Queue <ShortestPathVertex>();
foreach (var sourceVertex in sourceVertexes)
{
queue.Enqueue(spGraph.AddVertex(sourceVertex, 0));
}
while (queue.Any())
{
var from = queue.Dequeue();
foreach (var edge in graph.Vertexes[from.Id].Edges)
{
if (!takeEdge(edge))
{
continue;
}
if (spGraph.Vertexes.ContainsKey(edge.To))
{
var to = spGraph.Vertexes[edge.To];
if (to.Distance == from.Distance + 1)
{
spGraph.AddEdge(edge);
}
else if (to.Distance == from.Distance && from.Id < to.Id)
{
spGraph.AddSameLayerEdge(edge);
}
continue;
}
spGraph.AddEdge(edge);
queue.Enqueue(spGraph.AddVertex(edge.To, from.Distance + 1));
}
}
return(spGraph);
}
