title: How to print out a slash (/ or \) in C?
body: <p>I know this is a very silly and simple question but I've been trying to print out an image of a robot that should output this:</p>
  
  <pre><code>+----------+
  |          |
  | /\    /\ |
  | \/    \/ |
  |          |
  |  [-=-=-] |
  +----------+
  </code></pre>
  
  <p>The part I'm stuck on is printing out the eyes.
  originally I coded:</p>
  
  <pre><code>printf("| /\  /\ |");
  printf("| \/  \/ |");
  </code></pre>
  
  <p>but an error showed, so I remembered that you need to double slash so:</p>
  
  <pre><code>printf("| \/\\  \/\\ |");
  printf("| \\\/  \\\/ |");
  </code></pre>
  
  <p>but an error saying implicit declaration of function printf is showing even after that?! I don't understand the error. Can someone explain how to fix this please?</p>