// BFS from multiple sources
private void Bfs(Digraph G, IEnumerable <int> sources)
{
Queue <int> q = new Queue <int>();
foreach (int s in sources)
{
marked[s] = true;
distTo[s] = 0;
q.Enqueue(s);
}
while (q.Count != 0)
{
int v = q.Dequeue();
foreach (int w in G.GetAdj(v))
{
if (!marked[w])
{
edgeTo[w] = v;
distTo[w] = distTo[v] + 1;
marked[w] = true;
q.Enqueue(w);
}
}
}
}
// check that algorithm computes either the topological order or finds a directed cycle
private void Dfs(Digraph G, int v) // v is start vertex here
{
onStack[v] = true;
marked[v] = true;
foreach (int w in G.GetAdj(v))
{
// short circuit if directed cycle found
if (cycle != null)
{
return;
}
// found new vertex, so recur
else if (!marked[w])
{
edgeTo[w] = v;
Dfs(G, w);
}
// trace back directed cycle
else if (onStack[w])
{
cycle = new Stack <int>();
for (int x = v; x != w; x = edgeTo[x])
{
cycle.Push(x);
}
cycle.Push(w);
cycle.Push(v);
Debug.Assert(Check());
}
}
onStack[v] = false;
}
// --- dfs and pathes
private void Dfs(Digraph G, int v)
{
marked[v] = true;
foreach (int w in G.GetAdj(v))
{
if (!marked[w])
{
edgeTo[w] = v;
Dfs(G, w);
}
}
}
// DFS on graph G
private void Dfs(Digraph G, int v)
{
marked[v] = true;
id[v] = count;
foreach (int w in G.GetAdj(v))
{
if (!marked[w])
{
Dfs(G, w);
}
}
}
// --- Depth first search
private void Dfs(Digraph G, int s)
{
Count++;
marked[s] = true;
foreach (int w in G.GetAdj(s))
{
if (!marked[w])
{
Dfs(G, w);
}
}
}
private void Dfs(Digraph G, int v)
{
marked[v] = true;
Pre.Enqueue(v);
foreach (int w in G.GetAdj(v))
{
if (!marked[w])
{
Dfs(G, w);
}
}
Post.Enqueue(v);
ReversePost.Push(v);
}