数据结构与算法(C#实现)系列---演示篇(二)

                            Heavenkiller(原创)

         public static void ShowGeneralTree_travel()

         {

              IEnumerator tmpIEnum;

              Tree.TraversalType travelType=0;

              //---------------------提示----------------------------

              Console.WriteLine("please choose a the No. of a item you want to travel:");

              Console.WriteLine("1.BreadthFirst----- 广度遍历");

              Console.WriteLine("2.PreDepthFirst-----前序遍历");

              Console.WriteLine("3.InDepthFirst----中序遍历");

              Console.WriteLine("4.PostDepthFirst----后序遍历");

              switch(Console.ReadLine())

              {

                   case "1"://Show Stack

                       travelType=Tree.TraversalType.Breadth;

                       Console.WriteLine("广度遍历");

                       break;

                   case "2"://SortedList

                       travelType=Tree.TraversalType.PreDepth;

                       Console.WriteLine("前序遍历");

                       break;

                   case "3":

                       travelType=Tree.TraversalType.InDepth;

                       Console.WriteLine("中序遍历");

                       break;

                   case "4":

travelType=Tree.TraversalType.PostDepth;

                       Console.WriteLine("后序遍历");

                       break;

                   default:

                       break;

              }

              //构造一棵广义树 generaltree

              GeneralTree A=new GeneralTree("A");

              GeneralTree B=new GeneralTree("B");

              GeneralTree C=new GeneralTree("C");

              GeneralTree D=new GeneralTree("D");

              GeneralTree E=new GeneralTree("E");

              GeneralTree F=new GeneralTree("F");

                       A.AttackSubtree(B);

              A.AttackSubtree(C);

              B.AttackSubtree(D);

              B.AttackSubtree(E);

              A.AttackSubtree(F);

              //show the operation

              Console.WriteLine("A.AttackSubtree(B)");

              Console.WriteLine("A.AttackSubtree(C)");

              Console.WriteLine("B.AttackSubtree(D)");

              Console.WriteLine("B.AttackSubtree(E)");

              Console.WriteLine("A.AttackSubtree(F)");

//--------------------------------------------------------

              A.SetTraversalType(travelType);//设置遍历类型

              tmpIEnum=A.GetEnumerator();

              //Console.WriteLine("begin to depthfist travel:");

              while(tmpIEnum.MoveNext())

              {

                   Console.WriteLine(tmpIEnum.Current.ToString());

              }

         }

         public static void ShowStack_RPNCalCulator()

         {

              //read a expression string and push every character into the stack in queue.

              Console.WriteLine("this is performance for stack,you can input a string like this '123*+',then this subprogramme can compute it and get the result '7',this is RPN calculator. ");

              Console.WriteLine("please input a expression string:");

              string strExpression=Console.ReadLine();

              char [] tmpChars=strExpression.ToCharArray(0,strExpression.Length);

              Stack stackRPN=new Stack();

              int numA,numB;

              foreach(char tmp in tmpChars)

              {

                   switch (tmp)

                   {

                       case '*':

                            numA=(int)stackRPN.Pop();

                            numB=(int)stackRPN.Pop();

                            stackRPN.Push(numA*numB);

                            break;

                       case '+':

                            numA=(int)stackRPN.Pop();

                            numB=(int)stackRPN.Pop();

                            stackRPN.Push(numA+numB);

                            break;

                       default:

                            stackRPN.Push(Int32.Parse(tmp.ToString()));

                            break;

                   }

              }

              Console.WriteLine("the result is:{0}",stackRPN.Pop().ToString());

          }