コード例 #1
0
 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;
 }
コード例 #2
0
 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;
         }
     }
 }
コード例 #3
0
 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);
 }
コード例 #4
0
 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]);
             }
         }
     }
 }
コード例 #5
0
 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
         }
     }
 }