public void ShouldThrowExceptionBecauseTheFirstTownInRouteIsNotTheLastTownInPath()
{
// Arrange
var ab = new Route("AB5");
var xy = new Route("XY7");
var path = new TraveledPath(ab);
// Act
path.Append(xy);
}
public void ShouldntThrowException()
{
// Arrange
var route = new Route("AB5");
// Act
var traveledPath = new TraveledPath(route);
new TraveledPath(traveledPath);
}
/// <summary>
/// Travel through all possible paths in the graph.
/// </summary>
/// <param name="graph">Graph being traveled.</param>
/// <param name="visited">Already visited paths.</param>
/// <param name="destiny">Destiny town.</param>
/// <param name="maxStops">Maximum number of stops allowed (optional).</param>
/// <returns>All possible paths in the graph to the given destiny.</returns>
private IEnumerable <TraveledPath> TravelPaths(
Graph graph, IEnumerable <TraveledPath> visited, Town destiny, int?maxStops = null)
{
// Visits performed on this method call
var currentVisit = new List <TraveledPath>();
foreach (var path in visited)
{
// If we reached the maximum number of stops
if (maxStops.HasValue && path.Stops >= maxStops.Value)
{
continue;
}
// Current iteration town
var town = path.LastTown;
// Routes to current town neighbors
var neighborRoutes = graph.GetRoutesToNeighbors(town);
foreach (var neighborRoute in neighborRoutes)
{
// The neighbor town
var neighborTown = neighborRoute.Towns.Item2;
// Flag indicating if destiny has been reached
var reachedDestiny = neighborTown == destiny;
// Flag indicating if the neighbor has already been visited
var newVisit = !path.Contains(neighborTown);
if (reachedDestiny || newVisit)
{
// Path with the current neighbor
var neighborPath = new TraveledPath(path).Append(neighborRoute);
// Traveling through neighbor's neighbors
var neighborVisits = new List <TraveledPath> {
neighborPath
};
var neighborPaths = TravelPaths(graph, neighborVisits, destiny, maxStops);
// Adding neighbor's visits to this method call current visits
currentVisit.AddRange(neighborPaths);
// Adding this visit to current visits if destiny has been reached
if (reachedDestiny)
{
currentVisit.Add(neighborPath);
}
}
}
}
return(currentVisit);
}
public void ShouldCheckEquality()
{
// Arrange
var ab = new Route("AB1");
var bc = new Route("BC2");
var cd = new Route("CD3");
var path1 = new TraveledPath(ab).Append(bc).Append(cd);
var path2 = new TraveledPath(ab).Append(bc).Append(cd);
// Assert
Assert.AreEqual(path1, path2);
}
public void ShouldReturnQuantityOfStops()
{
// Arrange
var ab = new Route("AB1");
var bc = new Route("BC2");
var cd = new Route("CD3");
var path = new TraveledPath(ab);
// Act
path.Append(bc).Append(cd);
// Assert
Assert.AreEqual(3, path.Stops);
}
public void ShouldContainsTown()
{
// Arrange
var ab = new Route("AB1");
var bc = new Route("BC2");
var cd = new Route("CD3");
var b = new Town('B');
var path = new TraveledPath(ab);
// Act
path.Append(bc).Append(cd);
// Assert
Assert.IsTrue(path.Contains(b));
}
public void ShouldReturnLastTown()
{
// Arrange
var ab = new Route("AB1");
var bc = new Route("BC2");
var cd = new Route("CD3");
var d = new Town('D');
var path = new TraveledPath(ab);
// Act
path.Append(bc).Append(cd);
// Assert
Assert.AreEqual(path.LastTown, d);
}
public void ShouldFormatStringCorrectly()
{
// Arrange
var ab = new Route("AB1");
var bc = new Route("BC2");
var cd = new Route("CD3");
var d = new Town('D');
var path = new TraveledPath(ab);
// Act
path.Append(bc).Append(cd);
// Assert
Assert.AreEqual("A-B-C-D (3 stops, distance 6)", path.ToString());
}
public IEnumerable <TraveledPath> Find(Graph graph, Town origin, Town destiny, int?maxStops = null)
{
// Listing one stop neighbors as visited (required to travel further)
var visited = new List <TraveledPath>();
foreach (var neighborRoute in graph.GetRoutesToNeighbors(origin))
{
var path = new TraveledPath(neighborRoute);
visited.Add(path);
}
// Traveling
var availableRoutes = TravelPaths(graph, visited, destiny, maxStops);
// Sorting and returning
return(from availableRoute in availableRoutes
orderby availableRoute.Stops, availableRoute.Distance
select availableRoute);
}
