C Plus Plus Project : Salary

Cpp Project: Salary

 #include<iostream>  
 #include<string.h>  
 #include<stdlib.h>  
 #include<stdio.h>  
 #include<conio.h>  
 #include<fstream>  
 using namespace std;  
 class salary  
 {  
    float a;  
    fstream file;  
    char ch;  
 public:  
   char t;  
   void show(int);  
   void final(char m[20]);  
 };  
 void salary ::final(char m[20])  
   {  
   file.open(m,ios::in);  
   if(!file)  
    {  
    cout<<"invalid name.";  
    }  
   else  
   {  
    (file)  
     ;{  
     file.get(ch);  
     cout<<ch;  
     }  
   }  
   }  
 void salary ::show(int a)  
   {  
   if(a==1)  
   cout<<"\n\nThe person gets 1000 to 2000$ are \n\tOpu\n\tSahin\n\nto show their information enter name::\n";  
   if(a==2)  
   cout<<"\n\nThe person gets 2000 to 3000$ are \n\tomor\n\Wasif\n\nto show their information enter name::\n";  
   if(a==3)  
   cout<<"\n\nThe person gets 3000 to 4000$ are \n\tkabir\n\tmasud\nto show thrir information enter name::\n";  
   }  
 class sal_1:public salary  
 {  
  public:  
 };  
 class sal_2:public salary  
 {  
   public:  
 };  
 class sal_3:public salary  
 {  
   public:  
 };  
 int main()  
 {  
    int a;  
    char m[20];  
    while(1)  
    {  
    cout<<"\nif you want to exit press 0\n\nsalary starts 1000$ to 4000$\n\n enter you salary::";  
    cin>>a;  
   if(a>=1000 && a<=1999)  
    {  
     cout<<"\nyour salary lies between 1000 to 2000$";  
     sal_1 s1;  
     s1.show(1);  
     cin>>m;  
     strcat(m,".txt");  
     s1.final(m);  
      getch();  
    }  
    else if(a>=2000 && a<=2999)  
    {  
     cout<<"\nyour salary lies between 2000 to 3000$";  
     sal_2 s2;  
     s2.show(2);  
     cin>>m;  
     strcat(m,".txt");  
     s2.final(m);  
     getch();  
    }  
    else if(a>=3000 && a<=4000)  
    {  
     cout<<"\nyour salary lies between 3000 to 4000$";  
     sal_3 s3;  
     s3.show(3);  
     cin>>m;  
     strcat(m,".txt");  
     s3.final(m);  
     getch();  
    }  
    else if(a==0)  
    break;  
    else if(a>>4001 && a<<999)  
    {  
    cout<<"invalid ammount.";  
    getch();  
    }  
    }  
 return 0;  
 }