广度优先遍历 C#

using System.Collections;using System.Collections.Generic;namespace ConsoleApp1{    class SimpleGraph    {        public SimpleGraph()        {            // 初始化边表            edges = new Dictionary<char, char[]>();        }        public Dictionary<char, char[]> edges;        public char[] neighbors(char id)        {            return edges[id];        }    }    class Program    {        static void Main(string[] args)        {            // 初始化图            SimpleGraph example_graph = new SimpleGraph();            char[] A = { 'B' };            char[] B = { 'A', 'C', 'D' };            char[] C = { 'A' };            char[] D = { 'E', 'A' };            char[] E = { 'B' };            example_graph.edges.Add('A', A);            example_graph.edges.Add('B', B);            example_graph.edges.Add('C', C);            example_graph.edges.Add('D', D);            example_graph.edges.Add('E', E);            breadthFirstSearch(example_graph, 'A');            // 防止退出            Console.ReadKey();        }        private static void breadthFirstSearch(SimpleGraph graph, char start )        {            // 初始化队列            Queue queue = new Queue();            queue.Enqueue(start);            Dictionary<char, bool> visited = new Dictionary<char, bool>();            visited[start] = true;            while (queue.Count != 0)            {                char current = (char)queue.Dequeue();                Console.WriteLine("Visiting: " + current );                foreach (char next in graph.neighbors(current))                {                    if (!visited.ContainsKey(next))                    {                        queue.Enqueue(next);                        visited[next] = true;                    }                }            }        }    }}