类的派生

#include<iostream>
#include<fstream>
#include<string> 
using namespace std;
#define maxlen 100

//---------------------------------基类-------------------------------------
class Teacher{//基类
public:
    //Teacher(string name,string position);
    virtual int CaleSalary() const = 0;//纯虚函数,计算教师工资
    virtual void Show() const = 0;//纯虚函数，输出教师的姓名、职称、工资
    string name;//姓名
    string position;//职称
    int Salary;//工资
};
//---------------------------------基类-------------------------------------


//---------------------------------助教类-----------------------------------
//助教
class Assistant:public Teacher{
public:
    Assistant(string name,string position);//构造函数
    virtual int CaleSalary()const ;//计算教师工资
     virtual void Show()const;//输出教师的姓名、职称、工资
};

//Assistant(助教)构造函数
Assistant::Assistant(string Name,string Position)
{
    name = Name;
    position = Position;
}

//Assistant(助教)//计算教师工资
int Assistant::CaleSalary()const
{
    int temp;
    if(position=="助教"){
        temp = 900;
    }else if(position=="讲师"){
        temp = 1000;
    }else if(position=="副教授"){
        temp = 1300;
    }else if(position=="教授"){
        temp = 1600;
    }
    
    return temp;

}


//Assistant(助教)//输出显示
void Assistant::Show()const
{
    cout<<"姓名: "<<name<<", 职称: "<<position<<", 工资: "<<Salary<<"元"<<endl;
}


//---------------------------------助教类-----------------------------------



//---------------------------------讲师类-----------------------------------

//讲师类
class Lecture:public Teacher{
public:
    Lecture(string name,string position);//构造函数
    virtual int CaleSalary()const;//计算教师工资
    virtual void Show()const;//输出教师的姓名、职称、工资
};

//Lecture(讲师)构造函数
Lecture::Lecture(string Name,string Position)
{
    name = Name;
    position = Position;
}

//Lecture(讲师)//计算教师工资
int Lecture::CaleSalary()const
{
    int temp;
    if(position=="助教"){
        temp = 900;
    }else if(position=="讲师"){
        temp = 1000;
    }else if(position=="副教授"){
        temp = 1300;
    }else if(position=="教授"){
        temp = 1600;
    }
    
    return temp;;
}


//Lecture(讲师)：输出显示
void Lecture::Show()const
{
    cout<<"姓名: "<<name<<", 职称: "<<position<<", 工资: "<<Salary<<"元"<<endl;
}
//---------------------------------讲师类-----------------------------------




//---------------------------------副教授类---------------------------------

//副教授类(AssociateProfessor)
class AssociateProfessor:public Teacher{
public:
    AssociateProfessor(string name,string position);//构造函数
    virtual int CaleSalary()const;//计算教师工资
    virtual void Show()const;//输出教师的姓名、职称、工资
};

//副教授类(AssociateProfessor)构造函数
AssociateProfessor::AssociateProfessor(string Name,string Position)
{
    name = Name;
    position = Position;
}

//副教授类(AssociateProfessor)//计算教师工资
int AssociateProfessor::CaleSalary()const
{
    int temp;
    if(position=="助教"){
        temp = 900;
    }else if(position=="讲师"){
        temp = 1000;
    }else if(position=="副教授"){
        temp = 1300;
    }else if(position=="教授"){
        temp = 1600;
    }
    
    return temp;
}


//副教授类(AssociateProfessor)//输出显示
void AssociateProfessor::Show()const
{
    cout<<"姓名: "<<name<<", 职称: "<<position<<", 工资: "<<Salary<<"元"<<endl;
}
//---------------------------------副教授类---------------------------------

//---------------------------------教授类-----------------------------------

//Proffessor(教授类)
class Proffessor:public Teacher{
public:
    Proffessor(string name,string position);//构造函数
    virtual int CaleSalary()const;//计算教师工资
    virtual void Show()const;//输出教师的姓名、职称、工资
};

//Proffessor(教授类)构造函数
Proffessor::Proffessor(string Name,string Position)
{
    name = Name;
    position = Position;
}

int Proffessor::CaleSalary()const
{
    int temp;
    if(position=="助教"){
        temp = 900;
    }else if(position=="讲师"){
        temp = 1000;
    }else if(position=="副教授"){
        temp = 1300;
    }else if(position=="教授"){
        temp = 1600;
    }
    
    return temp;
}


//Proffessor(教授类)输出显示
void Proffessor::Show()const
{
    cout<<"姓名: "<<name<<", 职称: "<<position<<", 工资: "<<Salary<<"元"<<endl;
}
//---------------------------------教授类-----------------------------------

struct Total
{
    string name;
    string position;
    int salary;
};
Total Data[maxlen];
int num;//几组数据

void analyse(ifstream &in)
{ 
    int i;
    string s="";//初始字符串s为空
    char ch;//字符
    string str[maxlen];//存放字符串
    int count = 0;
    while(!in.eof())//当文件没读完
    {
        ch=in.get();//读入字符
        if(ch!='\n'&&ch!=' ')//当前字符不死空格或者换行符
        {
            s +=ch;//加入到字符串尾部
        }else {//是空格或换行符
            str[count] =s;
            count++;//计数+1
            s ="";//字符冲为空
        }
     }

    num = 0;//统计行数
    for(i=0;i<count;i=i+2)
    {
        Data[num].name = str[i];//姓名
        Data[num].position = str[i+1];//职称
        Data[num].salary = 0;//工资初始化为0
        num++;//行数+1
    }
}


int main() 
{  
    int i;
    ifstream in; 
    ofstream out;
/*
    char a[30];
    cout<<"请输入文件名:";
    cin>>a;
    in.open(a,ios::in); //打开文件
*/
    in.open("D:/teacher.txt",ios::in); //打开文件
    if(in.is_open()){
        analyse(in);   
        in.close();
    }else printf("文件操作出错!\n"); 

    out.open("D:/Teache.txt");//将某些关键词替换后的字符串存到文件中
     if(out.is_open())//打开文件
    {
        for( i=0;i<num;i++)
        {
            if(Data[i].position=="助教")
            {
                Teacher  *assistant = new Assistant(Data[i].name,Data[i].position);
                assistant->Salary =assistant->CaleSalary();
                assistant->Show();
                out<<assistant->name;
                out<<" ";
                out<<assistant->position;
                out<<" ";
                out<<assistant->Salary;
                out<<"\n";
     
            }else if(Data[i].position=="讲师")
            {
                Teacher *lecture = new Lecture(Data[i].name,Data[i].position);
                
                lecture->Salary =lecture->CaleSalary();
                lecture->Show();
                out<<lecture->name;
                out<<" ";
                out<<lecture->position;
                out<<" ";
                out<<lecture->Salary;
                out<<"\n";
            }else if(Data[i].position=="副教授")
            {
                Teacher *associateProfessor = new AssociateProfessor (Data[i].name,Data[i].position);
                associateProfessor->Salary =associateProfessor->CaleSalary();
                associateProfessor->Show();
                out<<associateProfessor->name;
                out<<" ";
                out<<associateProfessor->position;
                out<<" ";
                out<<associateProfessor->Salary;
                out<<"\n";
                
            }else if(Data[i].position=="教授")
            {
                Teacher *proffessor = new Proffessor (Data[i].name,Data[i].position);
                proffessor->Salary =proffessor->CaleSalary();
                proffessor->Show();
                out<<proffessor->name;
                out<<" ";
                out<<proffessor->position;
                out<<" ";
                out<<proffessor->Salary;
                out<<"\n";
            }
        }
     }else printf("文件操作出错!\n"); //文件带卡失败
    return 0;
}