public double calc(int amount, string fromUnit, string toUnit)
{
var from = (Units) Enum.Parse(typeof (Units), fromUnit.Replace("in", "inch"));
var to = (Units) Enum.Parse(typeof (Units), toUnit.Replace("in", "inch"));
var dgraf = new Graf<Units>();
var ftVertex = new Vertex<Units>(Units.ft);
var inVertex = new Vertex<Units>(Units.inch);
var ydVertex = new Vertex<Units>(Units.yd);
var miVertex = new Vertex<Units>(Units.mi);
ftVertex.AddDirectedEdge(12, inVertex);
inVertex.AddDirectedEdge(1D / 12, ftVertex);
ydVertex.AddDirectedEdge(3, ftVertex);
ftVertex.AddDirectedEdge(1D / 3, ydVertex);
miVertex.AddDirectedEdge(1760, ydVertex);
ydVertex.AddDirectedEdge(1D / 1760, miVertex);
dgraf.AddVertex(ftVertex);
dgraf.AddVertex(inVertex);
dgraf.AddVertex(ydVertex);
dgraf.AddVertex(miVertex);
var source = dgraf.Vertexes.FirstOrDefault(vertex => vertex.Key == from);
var target = dgraf.Vertexes.FirstOrDefault(vertex => vertex.Key == to);
var vertexPath = dgraf.GetBreadthPath(source, target).ToList();
var edgePath = new System.Collections.Generic.Stack<Edge<Units>>();
if (target.Color != Vertex<Units>.VertexColor.Black)
return 0;
var currentVertex = target;
while (currentVertex != null && currentVertex != source && currentVertex.Parent != null)
{
var currentEdge = currentVertex.Parent.Edges.FirstOrDefault(edge => edge.Target == currentVertex);
edgePath.Push(currentEdge);
currentVertex = currentVertex.Parent;
}
if (source == target)
return amount;
if (!edgePath.Any())
return 0;
double res = amount;
double weigth = 1;
foreach (var pathEdge in edgePath)
weigth *= pathEdge.Weigth;
return res * weigth;
}