title: How to include a file from another folder?
body: <p>In my current project I have separated my class files and my header files. My project structure currently looks like this:</p>
  
  <ul>
  <li><p>Project</p></li>
  <li><ul>
  <li>Source 
  <ul>
  <li>src
  <ul>
  <li>class1.cpp</li>
  <li>class2.cpp</li>
  </ul></li>
  <li>main.cpp</li>
  </ul></li>
  </ul></li>
  <li><ul>
  <li>Header
  <ul>
  <li>include
  <ul>
  <li>class1.h</li>
  <li>class2.h</li>
  </ul></li>
  </ul></li>
  </ul></li>
  </ul>
  
  <p>My problem is that I do not know how to include the header files into the class files. Am I unable to link to headers that are not at the same level or in a child folder? Or is there some way to go from the project root and work my way down? For instance:<br>
  <code>#include "Project/Headers/include/class1.h"</code> inside the class1.cpp file</p>