title: Check if two areas are in contact
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/1551243/finding-the-overlapping-area-of-two-rectangles-in-c">Finding the overlapping area of two rectangles (in C#)</a>  </p>
  </blockquote>
  
  
  
  <p>I have two areas identified by top left and bottom right corners (fig.1).</p>
  
  <p>In c#, how can I test if they are in contact (fig.2)?</p>
  
  <p><img src="https://i.stack.imgur.com/vWAmM.jpg" alt="enter image description here"></p>