title: #include parent directory's file
body: <p>My folder structure is </p>
  
  <pre><code>libA
      x.h
      y.h
      algorithm/
          a.h
  </code></pre>
  
  <p>Now in <code>a.h</code> I have <code>#include "libA/x.h"</code> which is not working. Its searching for <code>algorithm/libA/x.h</code>. So should I use <code>#include "../x.h"</code> ? Is the second option a bad design ? currently libA is header only. but latter I may choose to compile it as a library</p>
  
  <p>I am using cmake So can I or Should I add <code>libA</code> in my include path ?</p>
  
  <h2>In short</h2>
  
  <p>some files in My algorithm directory needs to include definitions from its parent folder. I cannot make all functions templated because the types are obvious and it will be overdoing. 
  So How should I design My project ?</p>