private void Dfs(EdgeWeightedDigraph G, int v)//(加权有向图)寻找相连的顶点
{
onStack[v] = true;
marked[v] = true;
foreach (DirectedEdge w in G.Adj(v))
{
if (this.HasCycle())
{
return;
}
else if (!marked[w.To()])
{
edgeTo[w.To()] = v;//存储最先到达w.To()点的v点
Dfs(G, w.To());
}
else if (onStack[w.To()])
{
cycle = new Stack <int>();
for (int x = v; x != w.To(); x = edgeTo[x])
{
cycle.Push(x);
}
cycle.Push(w.To());
cycle.Push(v);
}
}
onStack[v] = false;
}
private void Relax(EdgeWeightedDigraph G, int v)
{
foreach (DirectedEdge e in G.Adj(v))
{
int w = e.To();
if (distTo[w] > distTo[v] + e.Weight())
{
distTo[w] = distTo[v] + e.Weight();
edgeTo[w] = e;
}
}
}
private void Dfs(EdgeWeightedDigraph G, int v)
{
pre.enqueue(v);
marked[v] = true;
foreach (DirectedEdge w in G.Adj(v))
{
if (!marked[w.To()])
{
Dfs(G, w.To());
}
}
post.enqueue(v);
reversePost.Push(v);
}
private void Relax(EdgeWeightedDigraph G, int v)
{
foreach (DirectedEdge e in G.Adj(v))
{// v->w e:v和w相连的边
int w = e.To();
if (distTo[w] > distTo[v] + e.Weight())
{// 起点到达w点的路径 > 起点到达v的路径+e的权重
distTo[w] = distTo[v] + e.Weight();
edgeTo[w] = e;
if (pq.Contains(w))
{
pq.Change(w, distTo[w]);
}
else
{
pq.Insert(w, distTo[w]);
}
}
}
}
private void Relax(EdgeWeightedDigraph G, int v)
{
foreach (DirectedEdge e in G.Adj(v))
{
int w = e.To();
if (distTo[w] > distTo[v] + e.Weight())
{
distTo[w] = distTo[v] + e.Weight();
edgeTo[w] = e;
if (!onQ[w])
{
queue.enqueue(w);
onQ[w] = true;
}
}
if (cost++ % G.VNumber() == 0)
{
FindNegativeCycle();//寻找有向图中是否有负权重环，以保证循环能够结束
}
}
}
