f0812.cpp

it is a usefull thing

//=====================================
// f0812.cpp
// misuse data member
//=====================================
#include<iostream>
using namespace std;
//-------------------------------------
class Student{
  int n;
  string name;
public:
  void set(string str){
    static int number = 0;
    name = str;
    n = ++number;
  }
  void print(){ cout<<name<<" -> students are "<<n<<" numbers\n";  }
};//-----------------------------------
void fn(){
  Student s1;
  s1.set("Jenny");
  Student s2;
  s2.set("Randy");
  s1.print();
}//------------------------------------
int main(){
  Student s;
  s.set("Smith");
  fn();
  s.print();
}//====================================