/// <summary>
/// Visits all recheable nodes in correct order.
/// </summary>
/// <remarks>
/// Graph must be directed, acyclic.
/// </remarks>
/// <typeparam name="T">The type of graph vertex.</typeparam>
/// <param name="node">The beginning node.</param>
/// <param name="graph">The graph structure.</param>
/// <returns>Listed nodes in correct order.</returns>
public static List <uint> ListNodesInOrder(uint node, [NotNull] IGraph graph)
{
List <uint> orderedNodes = new List <uint>();
// We keep track of visited nodes and how many times they were visited.
// We proceed when count is the same as number of links to that node.
List <VisitedNode> visitedNode = new List <VisitedNode>(10);
Stack <SearchData> stack = new Stack <SearchData>();
stack.Push(new SearchData(node, graph.NextNodes(node)));
// We also add first.
orderedNodes.Add(node);
// Until we finish.
while (true)
{
// We can exit.
if (stack.Count == 0)
{
break;
}
SearchData search = stack.Pop();
if (search.Next(out node))
{
// It is still useful.
stack.Push(search);
// We have next in node. We check if we can proceed.
uint order = graph.Order(node);
if (order == 1)
{
// We can insert it here, it is ordered.
orderedNodes.Add(node);
stack.Push(new SearchData(node, graph.NextNodes(node)));
continue;
}
// We have to make sure we add the count to visited. First check
// if it exists.
bool found = false;
for (int i = 0; i < visitedNode.Count; ++i)
{
// We found it.
if (visitedNode[i].node == node)
{
visitedNode[i].visitCount++;
if (visitedNode[i].visitCount >= order)
{
// We can insert it here, it is ordered.
orderedNodes.Add(node);
stack.Push(new SearchData(node, graph.NextNodes(node)));
}
found = true;
break;
}
}
// We may already found it.
if (found)
{
continue;
}
// We must add it if not found.
VisitedNode vnode = new VisitedNode();
vnode.node = node;
vnode.visitCount = 1;
visitedNode.Add(vnode);
}
}
return(orderedNodes);
}