新手写的四则运算，觉得效率不怎么样，哪位有耐心的大大可以提点意见~

[KID_coder]

//MainFile
#include <iostream>
#include "MyCalculator.h"
#include "MyCalculator.cpp"
using namespace std;
void main()
{
    Operand *TopNum,*BaseNum;         //初始化栈顶和栈底
	TopNum = new Operand;
	BaseNum = new Operand;
	TopNum->next = BaseNum->next = NULL;
	TopNum = BaseNum;
	Operator *TopOpera,*BaseOpera;
	TopOpera = new Operator;
	BaseOpera = new Operator;
	TopOpera->next = BaseOpera->next = NULL;
	TopOpera->Opera = BaseOpera->Opera = '!';
	TopOpera = BaseOpera;
	Welcome();

    char ch,Opera,OpOpera;
	int num,Value,TValue1,TValue2;
	ch = getchar();
    while(ch != '\n')
	{
		if (isdigit(ch))
		{
			ungetc(ch,stdin);
			scanf("%d",&num);
			PushNum(TopNum,num);
		}
        else
		{
			if((ch == ')' ||ch == '}' || ch == ']'))
			{
				switch(ch)
				{
				case ')' : OpOpera = '(';break;
				case ']' : OpOpera = '[';break;
				case '}' : OpOpera = '{';break;
				default : cout << "程序出现错误！\n";exit(1);
				}
				    while(OpOpera != TopOpera->Opera)
					{
						Opera = PopOpera(TopOpera);
						TValue1 = PopNum(TopNum);
						TValue2 = PopNum(TopNum);
						Value = Calculator(TValue1,TValue2,Opera);
						PushNum(TopNum,Value);
					}	
				Opera = PopOpera(TopOpera);
			}
			else
			{
				switch(Compare(TopOpera->Opera,ch))
					{
						case '>' : TValue1 = PopNum(TopNum);
                                   TValue2 = PopNum(TopNum);
								   Opera = PopOpera(TopOpera);
								   Value = Calculator(TValue1,TValue2,Opera);
								   PushNum(TopNum,Value);
								   PushOpera(TopOpera,ch);break;
						case '<' : PushOpera(TopOpera, ch);break; 
					//	case '=' : ch = PopOpera(TopOpera);break;
					//	case '@' : cout << "!!!!!!!!!!!!";break;
						default : cout << "compare函数错误，请检查是否输入正确。\n";break;//exit(1);
					}
			}
                
		}
		
		ch = getchar();
	
	} 
	while(TopOpera->Opera != '!')
			{
				Opera = PopOpera(TopOpera);
			    TValue1 = PopNum(TopNum);
                TValue2 = PopNum(TopNum);
				Value = Calculator(TValue1,TValue2,Opera);
				PushNum(TopNum,Value);
			}
   cout << ">> 计算所得结果是："<< Value << endl;
}


//MyCalculator.h
#ifndef MyMATH_H
#define MyMATH_H
class Operand                //操作数类
{ 

public :
	int num;
	Operand (){};
	Operand (int num) {this->num = num;}
    Operand *next;
	friend void PushNum(Operand * &Top,int Num);
	friend int PopNum(Operand * &Top);
};

class Operator                  //操作符类（运算符类）
{
public :
	char Opera;
	Operator(){}
	Operator(char Opera){this->Opera = Opera;}
	Operator *next;
	friend void PushOpera(Operator *&,char);
	friend char PopOpera(Operator *&);
};

void Welcome();     //欢迎界面
//void GetExp();     //获取用户输入的表达式
char Compare(char token1,char token2);  //比较运算符的优先级
int Calculator (int Num1,int Num2,char Opera);

#endif


//MyCalculator.cpp
#ifndef MyMATHH_H_
#define MyMATHH_H_
#include <iostream>
using namespace std;
void PushNum(Operand * &Top,int NewNum) //数字进栈操作！
{
	Operand *NewOperand;
	NewOperand = new Operand;
	NewOperand->num = NewNum;
	NewOperand->next = Top;
	Top = NewOperand;
}
int PopNum(Operand * &Top )
{
	int temp;
	Operand *NewTop;    //pop出之后，定义一个新的栈顶
	temp = Top->num;
        NewTop = Top->next;
        delete Top;
	Top = NewTop;
	return temp;
}
void PushOpera(Operator * &Top,char NewOpera)
{
  Operator *NewTop;    
  NewTop = new Operator;
  NewTop->Opera = NewOpera;
  NewTop->next = Top;
  Top = NewTop;
}
char PopOpera(Operator * &Top)
{
   char temp;
   temp = Top->Opera;
   Operator *NewTop;
   NewTop = Top->next;
   delete Top;
   Top = NewTop;
   return temp;
} 
char Compare(char token1,char token2)         //compare 函数比较优先级
{
	char ReValue;
	if ( token1 == '+' || '-' == token1  ) //比较优先级，判断运算先后
	{
		switch (token2)
		{
		case '+' : 
		case '-' : ReValue = '>';break; //加和减的优先级相同！
		case '*' :
		case '/' : 
		case '(' :
		case '[' :
		case '{' : ReValue = '<';break;
		default : break;
		}
	}
	else if (token1 == '*' || token1 == '/' )
	{
		switch (token2)
		{
		case '+' :
		case '-' : 
		case '*' :
		case '/' :ReValue = '>';break;
		case '(' :
		case '[' :
		case '{' : ReValue = '<';break;
		default : ReValue = '#';break;
		}
	}
	else if (token1 == '('  || token1 == '['  || token1 == '{'  )     
		{    
			ReValue = '<'; //遇到左括号，进栈操作~
		}

	else if (token1 == '!' )  
	{
	   
		ReValue = '<';	  //栈中无元素~~进栈！
	}
	else
		ReValue = '#';   
	return ReValue;
}
void Welcome()
{
	char line1[] = "\n\n\n\n\t\t\t     欢迎使用本计算器\n";
	char line2[] = "\t\t==========================================\n";
	int i(0);
	while(line1[i] != '\0')
	{
		_sleep(30);
		putchar(line1[i++]);
	}
	i = 0;
	while(line2[i] != '\0')
	{
		_sleep(30);
		putchar(line2[i++]);
	}
	cout << "\t\t请输入要计算的表达式，如4*(4+3)，然后回车结束\n\t\t\t\t\t\t(KID制作，测试版) \n";
	cout << "\t\t==========================================\n";
}

int Calculator (int Num2,int Num1,char Opera)         //注意次序~~Num1是前一个数，Num2是后一个数！
{
	int result;
	switch(Opera)
	{
	case '+' : result = Num1 + Num2;break;
	case '-' : result = Num1 - Num2;break;
	case '*' : result = Num1 * Num2;break;
	case '/' : result = Num1 / Num2; break;
	default : cout << "Calculator函数错误，请检查是否输入正确.\n";break;//exit(1);
	}
	return result;
}
#endif

[KID_coder]

我也说不清~~就是代码量太大了~
判断语句多了~

[sagegz]

LZ首先你自己觉得哪的效率不高呢？

[V68V6]

看看大话设计模式

第一篇就是讲一个四则计算器的设计和优化问题

你说的效率是指代码冗余

[cpio]

if((ch == ')' ||ch == '}' || ch == ']'))
{
switch(ch)
{
case ')' : OpOpera = '(';break;
case ']' : OpOpera = '[';break;
case '}' : OpOpera = '{';break;
default : cout << "程序出现错误！\n";exit(1);
}


这儿default后面的内容有没有意义啊？

[brucest0078]

用算符优先算法把。。。做一个operator 优先级矩阵表，然后在比较进出栈计算，
编译原理里面还有其他的