最短路径:Dijkstra算法 C#

     class Program
     {
         const int u = ;

         static void Main(string[] args)
         {
             Console.WriteLine("各点距离矩阵如下:");
             Console.WriteLine("   A  B  C  D  E");
             Console.WriteLine("A  0  2  3  /  /");
             Console.WriteLine("B  2  0  3  5  2");
             Console.WriteLine("C  3  3  0  2  4");
             Console.WriteLine("D  /  5  2  0  1");
             Console.WriteLine("E  /  2  4  1  0");
             int[,] matrix = new int[, ] { { , , , u, u }, { , , , ,  }, { , , , ,  }, { u, , , ,  }, { u, , , ,  } };
             while (true)
             {
                 Console.WriteLine("请输入要计算的起始点：");
                 string a = Console.ReadLine();
                 int start;
                 switch (a.ToLower())
                 {
                     default:
                     case "a":
                         start = ;
                         break;
                     case "b":
                         start = ;
                         break;
                     case "c":
                         start = ;
                         break;
                     case "d":
                         start = ;
                         break;
                     case "e":
                         start = ;
                         break;
                 }
                 var list = Dijkstra(matrix, start);

                 for (int i = ; i < list.Count; i++)
                 {
                     Console.WriteLine("从" + a.ToUpper() + "出发到" + i.IndexToChar() + "的最短距离为:" + list[i].Distance + ",最短路径为:" + list[i].Path);
                 }
             }
         }

         public static List<ShortPath> Dijkstra(int[,] matrix, int start)
         {
             int n = matrix.GetLength();
             int[] visited = new int[n];
             var list = new List<ShortPath>();

             for (int i = ; i < n; i++)
             {
                 list.Add(new ShortPath() { Index = i, Name = start.IndexToChar() + "->" + i.IndexToChar(), Path = start.IndexToChar() + "->" + i.IndexToChar(), Distance =  });
             }
             visited[start] = ;
             for (int i = ; i < n; i++)
             {
                 int k = -;
                 int dmin = u;
                 for (int j = ; j < n; j++)
                 {
                     if (visited[j] ==  && matrix[start, j] < dmin)
                     {
                         dmin = matrix[start, j];
                         k = j;
                     }
                 }

                 list[k].Distance = dmin;

                 visited[k] = ;
                 for (int j = ; j < n; j++)
                 {
                     if (visited[j] ==  && matrix[start, k] + matrix[k, j] < matrix[start, j])
                     {
                         matrix[start, j] = matrix[start, k] + matrix[k, j];
                         list[j].Path = list[k].Path + "->" + j.IndexToChar();
                     }
                 }
             }

             return list;
         }
     }

     public static class Common
     {
         /// <summary>
         /// 索引转换字母
         /// </summary>
         /// <param name="index">当前索引</param>
         /// <param name="startIndex">起始索引 默认0</param>
         /// <returns></returns>
         public static char IndexToChar(this int index, int startIndex = )
         {
             return (char)('A' + index - startIndex);
         }
     }

     public class ShortPath
     {
         private int index;
         private string name;
         private string path;
         private int distance;

         public string Path { get => path; set => path = value; }
         public int Distance { get => distance; set => distance = value; }
         public string Name { get => name; set => name = value; }
         public int Index { get => index; set => index = value; }
     }