title: Way to link 2 variables in a class in C++
body: <p>Say I wanted to have one variable in a class always be in some relation to another without changing the "linked" variable explicitly.</p>
  
  <p>For example: int foo is always 10 less than int bar.</p>
  
  <p>Making it so that if I changed bar, foo would be changed as well. Is there a way to do this? (Integer overflow isn't really possible so don't worry about it.)</p>
  
  <p>Example: (Obviously doesn't work, but general code for an understanding)</p>
  
  <pre><code>class A
  {
      int x;
      int y = x - 10; // Whenever x is changed, y will become 10 less than x
  };
  </code></pre>