text: #include <iostream>
  
  using namespace std;
  
  class Student {
    string name;
    int roll_no;
  
   public:
    static int student_count;
    void set(string s, int i) {
      name = s;
      roll_no = i;
      student_count++;
    }
    int get_count() { return student_count; }
  };
  
  int Student::student_count;
  
  int main() {
    Student a, b, c, d;
  
    a.set("A", 1);
    cout << "Student count: " << a.get_count() << endl;
  
    b.set("B", 2);
    cout << "Student count: " << a.get_count() << endl;
  
    c.set("C", 3);
    cout << "Student count: " << a.get_count() << endl;
  
    d.set("D", 4);
    cout << "Student count: " << b.get_count() << endl;
  }