title: C++ selecting N characters from string
body: <p>I have a String. Let it be <code>string a = "abcde";</code>.</p>
  
  <p>And I want to select only a few characters (Let me say from 1 to 3).</p>
  
  <p>In python I would do it like <code>a[1:3]</code>.
  But C++ doesn't allow me to do that. It only allows for example: <code>a[n]</code>, not a[n:x].</p>
  
  <p>Is there a way to select <code>n</code> characters from string in C++?</p>
  
  <p>Or do I need to do it with <code>erase()</code>? </p>