/// <summary>
/// 求解
/// </summary>
/// <returns></returns>
public Path resolve()
{
Path path = new Path();
Node start = new Node(p.Start);
LinkedList<Node> Open = new LinkedList<Node>();
HashSet <Node>Open2=new HashSet<Node> (); // 元素与Open一样。效率不同。
HashSet<Node> Close = new HashSet<Node>();
Open.AddFirst(start); // 起始点。
Open2.Add(start);
bool flag = false;
Node curr=null;
while(Open .Count >0)
{
curr = Open.First(); // 取出第一个。
Open.RemoveFirst();
Open2.Remove (curr);
Close.Add(curr); // 放入闭集合，后面会做重复性检查。
if (curr.cell.End)
{
flag = true;
break;
}
curr.Expand(Open, Open2, Close); //展开此节点：其所有的不在Open和Close的子节点，加入到队列尾部。
}
if (flag)
{
while(curr.Parent !=null)//记录下所有的结果。
{
path.cells.Add(curr.cell);
curr = curr.Parent;
}
path.cells.Add(curr.cell);//这是第一个点。
}
return path;
}
/// <summary>
/// 已经选择了某节点next后，将其在数据结构中进行安置。
/// Open 必须为双向链表。
/// Open2 是为了定位效率。
/// </summary>
/// <param name="next"></param>
/// <param name="Open"></param>
/// <param name="Open2"></param>
/// <param name="Close"></param>
public void Conduct(Node next,LinkedList<Node>Open,HashSet <Node >Open2,HashSet <Node>Close)
{
if (!Open2.Contains(next) && !Close.Contains(next))
{
Open.AddLast(next);
Open2.Add(next);
this.Children.Add(next);
next.Parent = this;
}
}
public Path resolve(int pdepth)
{
Path path = new Path();
Node start = new Node(p.Start);
start.Depth = 0;
LinkedList<Node> Open = new LinkedList<Node>();
HashSet<Node> Open2 = new HashSet<Node>();
HashSet<Node> Close = new HashSet<Node>();
Open.AddFirst(start);
Open2.Add(start);
bool flag = false;
Node curr = null;
while (Open.Count > 0)
{
curr = Open.First();
Open.RemoveFirst();
Open2.Remove(curr);
Close.Add(curr);
if (curr.cell.End)
{
flag = true;
break;
}
if(curr.Depth < pdepth )
curr.ExpandDF(Open, Open2, Close);
}
if (flag)
{
while (curr.Parent != null)
{
path.cells.Add(curr.cell);
curr = curr.Parent;
}
path.cells.Add(curr.cell);
}
else
;
return path;
}
/// <summary>
/// 是否为某节点的祖先。
/// </summary>
/// <param name="offspring"></param>
/// <returns></returns>
public bool IsParentOf(Node offspring)
{
Node curr = offspring;
while (curr.Parent != null)
{
if (this.Equals(curr.Parent)) return true;
curr = curr.Parent;
}
return false;
}
/// <summary>
/// 对当前节点进行展开，使用深度优先。
/// </summary>
/// <param name="Open"></param>
/// <param name="Open2"></param>
/// <param name="Close"></param>
public void ExpandDF(LinkedList<Node> Open, HashSet<Node> Open2, HashSet<Node> Close)
{
Node curr = this;
if (curr.cell.UpStatus == WallStatus.open && curr.cell.upNei != null)
{
Node next = new Node(curr.cell.upNei);
curr.ConductDF(next, Open, Open2, Close);
}
if (curr.cell.DownStatus == WallStatus.open && curr.cell.downNei != null)
{
Node next = new Node(curr.cell.downNei);
curr.ConductDF(next, Open, Open2, Close);
}
if (curr.cell.LeftStatus == WallStatus.open && curr.cell.leftNei != null)
{
Node next = new Node(curr.cell.leftNei);
curr.ConductDF(next, Open, Open2, Close);
}
if (curr.cell.RightStatus == WallStatus.open && curr.cell.rightNei != null)
{
Node next = new Node(curr.cell.rightNei);
curr.ConductDF(next, Open, Open2, Close);
}
}