text: #include <iostream>
  
  using namespace std;
  
  int main() {
      int n = 5;
      int &r = n;
      int &k = r;
      int &i = k;
  
      cout << "n = " << n << " r = " << r << " k = " << k << " i = " << i << endl;
      n++;
      cout << "n = " << n << " r = " << r << " k = " << k << " i = " << i << endl;
      r++;
      cout << "n = " << n << " r = " << r << " k = " << k << " i = " << i << endl;
      k++;
      cout << "n = " << n << " r = " << r << " k = " << k << " i = " << i << endl;
      i++;
      cout << "n = " << n << " r = " << r << " k = " << k << " i = " << i << endl;
      return 0;
  }