/// <summary>
/// 初始化并运行广度优先搜索
/// </summary>
public static void BuildAndRunBFS()
{
// 定义节点关系
BFSNode root = new BFSNode(1, null, new BFSNode[] { });
BFSNode n2 = new BFSNode(2, root, new BFSNode[] { });
BFSNode n3 = new BFSNode(3, root, new BFSNode[] { });
BFSNode n4 = new BFSNode(4, n3, new BFSNode[] { });
BFSNode n5 = new BFSNode(5, n4, new BFSNode[] { });
BFSNode nk = new BFSNode(10, root, new BFSNode[] { n5 });
BFSNode n6 = new BFSNode(6, n5, new BFSNode[] { });
root.Nodes = new BFSNode[] { n2, n3, nk };
n3.Nodes = new BFSNode[] { n4 };
n4.Nodes = new BFSNode[] { n5 };
n5.Nodes = new BFSNode[] { n6 };
Console.WriteLine(BFS(root, n6));
}
/// <summary>
/// 广度优先搜索
/// </summary>
/// <param name="root">起始根节点</param>
/// <param name="target">目标节点</param>
/// <returns></returns>
private static int BFS(BFSNode root, BFSNode target)
{
Queue <BFSNode> queue = new Queue <BFSNode>();
queue.Enqueue(root);
int step = 0;
// 处理队列节点
while (queue.Count > 0)
{
// 处理路径步骤+1
step += 1;
int dealCount = queue.Count;
// 处理每个节点
for (int i = 0; i < dealCount; i++)
{
// 获取当前 队列 开始元素
var currentNode = queue.Peek();
// 如果为目标元素
if (currentNode.Equals(target))
{
// 返回步骤数
return(step);
}
// 否则 将 当前节点 下级节点 添加至队列中
for (int j = 0; j < currentNode.Nodes.Length; j++)
{
queue.Enqueue(currentNode.Nodes[j]);
}
// 当前元素 出列
queue.Dequeue();
}
}
return(-1);
}
public BFSNode(int number, BFSNode parent, IEnumerable <BFSNode> nodes)
{
this.Number = number;
this.Parent = parent;
this.Nodes = nodes.ToArray();
}