计算表达式 --堆栈

using System;
using System.Collections.Generic;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {

        static void Main(string[] args)
        {
            int a = 10;
            int b = 20;
            int c = 30;
            int d = 2;
            Stack<Object> oldStack = new Stack<Object>();
            Object[] obj = new Object[] { a, "*", "(", "(", b, "+", c, ")", "/", d, ")" };
            for (int i = obj.Length - 1; i >= 0; i--)
            {
                oldStack.Push(obj[i]);
                //Console.WriteLine(obj[i].ToString());
            }

            //前面正确
            Stack<Object> newStack = new Stack<Object>();
            while (oldStack.Count > 0)
            {
                Object o = oldStack.Pop();
              //  Console.WriteLine(oldStack.Count.ToString());
                if (o.ToString() != ")")
                {
                    //Console.WriteLine(o);
                    newStack.Push(o);
                }
                else
                {
                    Object temp1 = null;
                    Stack<Object> temp = new Stack<Object>();
                    temp1 = newStack.Pop();
                    while (temp1.ToString() != "(")
                    {
                        temp.Push(temp1);
                        temp1 = newStack.Pop();
                    }

                    Object[] temp2 = new Object[temp.Count];
                    int i = 0;
                    while (temp.Count != 0)
                    {
                        temp2[i] = temp.Pop();
                        i++;
                    }
                    for (int j = 0; j < i; j++)
                    {
                        string opt = temp2[j].ToString();
                        if (opt == "*")
                        {
                            int opd = Convert.ToInt32(temp2[j - 1]) * Convert.ToInt32(temp2[j + 1]);
                            Object[] temp3 = new Object[i - 2];
                            for (int m = 0; m < j - 1; m++)
                            {
                                temp3[m] = temp2[m];
                            }
                            temp3[j - 1] = opd;
                            for (int m = j + 2; m < j - 1; m++)
                            {
                                temp3[m - 2] = temp2[m];
                            }
                            temp2 = temp3;
                            i = temp2.Length;

                        }
                        if (opt == "/")
                        {
                            int opd = Convert.ToInt32(temp2[j - 1]) / Convert.ToInt32(temp2[j + 1]);
                            Object[] temp3 = new Object[i - 2];
                            for (int m = 0; m < j - 1; m++)
                            {
                                temp3[m] = temp2[m];
                            }
                            temp3[j - 1] = opd;
                            for (int m = j + 2; m < j - 1; m++)
                            {
                                temp3[m - 2] = temp2[m];
                            }
                            temp2 = temp3;
                            i = temp2.Length;

                        }
                    }
                    for (int j = 0; j < i; j++)
                    {
                        string opt = temp2[j].ToString();
                        if (opt == "+")
                        {
                            int opd = Convert.ToInt32(temp2[j - 1]) + Convert.ToInt32(temp2[j + 1]);
                            Object[] temp3 = new Object[i - 2];
                            for (int m = 0; m < j - 1; m++)
                            {
                                temp3[m] = temp2[m];
                            }
                            temp3[j - 1] = opd;
                            for (int m = j + 2; m < j - 1; m++)
                            {
                                temp3[m - 2] = temp2[m];
                            }
                            temp2 = temp3;
                            i = temp2.Length;

                        }
                        if (opt == "-")
                        {
                            int opd = Convert.ToInt32(temp2[j - 1]) - Convert.ToInt32(temp2[j + 1]);
                            Object[] temp3 = new Object[i - 2];
                            for (int m = 0; m < j - 1; m++)
                            {
                                temp3[m] = temp2[m];
                            }
                            temp3[j - 1] = opd;
                            for (int m = j + 2; m < j - 1; m++)
                            {
                                temp3[m - 2] = temp2[m];
                            }
                            temp2 = temp3;
                            i = temp2.Length;

                        }
                    }
                 //   Console.WriteLine(temp2[0]);
                    newStack.Push(temp2[0]);
                }
               // Console.WriteLine(newStack.Count.ToString());
                //Console.WriteLine(newStack.Pop());
              
            }
            object[] temp4 = new object[newStack.Count];
            int p=0;
            while (newStack.Count != 0)
            {
                temp4[p++] = newStack.Pop();
            }
            for (int j = 0; j < p; j++)
            {
                string opt = temp4[j].ToString();
                if (opt == "*")
                {
                    int opd = Convert.ToInt32(temp4[j - 1]) * Convert.ToInt32(temp4[j + 1]);
                    Object[] temp3 = new Object[p - 2];
                    for (int m = 0; m < j - 1; m++)
                    {
                        temp3[m] = temp4[m];
                    }
                    temp3[j - 1] = opd;
                    for (int m = j + 2; m < j - 1; m++)
                    {
                        temp3[m - 2] = temp4[m];
                    }
                    temp4 = temp3;
                    p = temp4.Length;

                }
                if (opt == "/")
                {
                    int opd = Convert.ToInt32(temp4[j - 1]) / Convert.ToInt32(temp4[j + 1]);
                    Object[] temp3 = new Object[p - 2];
                    for (int m = 0; m < j - 1; m++)
                    {
                        temp3[m] = temp4[m];
                    }
                    temp3[j - 1] = opd;
                    for (int m = j + 2; m < j - 1; m++)
                    {
                        temp3[m - 2] = temp4[m];
                    }
                    temp4 = temp3;
                    p = temp4.Length;

                }
            }
            for (int j = 0; j < p; j++)
            {
                string opt = temp4[j].ToString();
                if (opt == "+")
                {
                    int opd = Convert.ToInt32(temp4[j - 1]) + Convert.ToInt32(temp4[j + 1]);
                    Object[] temp3 = new Object[p - 2];
                    for (int m = 0; m < j - 1; m++)
                    {
                        temp3[m] = temp4[m];
                    }
                    temp3[j - 1] = opd;
                    for (int m = j + 2; m < j - 1; m++)
                    {
                        temp3[m - 2] = temp4[m];
                    }
                    temp4 = temp3;
                    p = temp4.Length;

                }
                if (opt == "-")
                {
                    int opd = Convert.ToInt32(temp4[j - 1]) - Convert.ToInt32(temp4[j + 1]);
                    Object[] temp3 = new Object[p - 2];
                    for (int m = 0; m < j - 1; m++)
                    {
                        temp3[m] = temp4[m];
                    }
                    temp3[j - 1] = opd;
                    for (int m = j + 2; m < j - 1; m++)
                    {
                        temp3[m - 2] = temp4[m];
                    }
                    temp4 = temp3;
                    p = temp4.Length;

                }
            }
            Console.WriteLine(temp4[0].ToString());
            Console.ReadKey();
        }
    }
}