public List <List <Vertex> > FindAllPaths(ComplexGraph g, int s, int t)
{
List <List <Vertex> > paths = new List <List <Vertex> >();
var vertex = g.Vertexes.First(x => x.Index == s);
Dfs(g, vertex, t, new List <Vertex>()
{
vertex
}, paths);
return(paths);
}
private void Dfs(ComplexGraph g, Vertex s, int t, List <Vertex> path, List <List <Vertex> > paths)
{
if (s.Index == t)
{
paths.Add(path);
}
foreach (var w in g.Adj(s.Index))
{
if (!path.Contains(w))
{
Dfs(g, w, t, new List <Vertex>(path)
{
w
}, paths);
}
}
}
public IEnumerable <Vertex> FindShortestPath(ComplexGraph g, int s, int t)
{
bool[] marked = new bool[g.Vertexes.Count];
var vertex = g.Vertexes.First(x => x.Index == s);
Queue <Vertex> queue = new Queue <Vertex>();
queue.Enqueue(vertex);
marked[s] = true;
Dictionary <Vertex, Vertex> pathDic = new Dictionary <Vertex, Vertex>();
bool find = false;
while (queue.Count > 0)
{
var v = queue.Dequeue();
foreach (var w in g.Adj(v.Index))
{
if (!marked[w.Index])
{
marked[w.Index] = true;
pathDic[w] = v;
queue.Enqueue(w);
if (w.Index == t)
{
find = true;
break;
}
}
}
if (find)
{
break;
}
}
var tVertex = g.Vertexes.First(x => x.Index == t);
Stack <Vertex> path = new Stack <Vertex>();
path.Push(tVertex);
while (pathDic.ContainsKey(tVertex))
{
tVertex = pathDic[tVertex];
path.Push(tVertex);
}
return(path);
}
public List <List <Vertex> > FindShortestPaths(ComplexGraph g, int s, int t)
{
List <List <Vertex> > paths = new List <List <Vertex> >();
Dictionary <Vertex, List <List <Vertex> > > pathDic = new Dictionary <Vertex, List <List <Vertex> > >();
var sVertex = g.Vertexes.First(x => x.Index == s);
pathDic[sVertex] = new List <List <Vertex> >()
{
new List <Vertex>()
{
sVertex
}
};
Queue <Vertex> queue = new Queue <Vertex>();
queue.Enqueue(sVertex);
while (queue.Count > 0)
{
var v = queue.Dequeue();
foreach (var w in g.Adj(v.Index))
{
var pathList = pathDic[v];
List <List <Vertex> > newPathList = new List <List <Vertex> >();
foreach (var path in pathList)
{
newPathList.Add(new List <Vertex>(path)
{
w
});
}
if (w.Index == t)
{
foreach (var newPath in newPathList)
{
if (paths.Count == 0)
{
paths.Add(newPath);
}
else if (paths[0].Count > newPath.Count)
{
paths = new List <List <Vertex> >()
{
newPath
};
}
else if (paths[0].Count == newPath.Count)
{
paths.Add(newPath);
}
}
continue;
}
if (pathDic.ContainsKey(w))
{
pathDic[w].AddRange(newPathList);
}
else
{
pathDic[w] = newPathList;
queue.Enqueue(w);
}
}
}
return(paths);
}
