title: How do I write a function in C?
body: <p>I'm learning C from the first section of <em>Objective-C Programming</em> by Aaron Hillegass. I'm trying to complete one of the the end-of-chapter challenges and can't seem to nail down the required function and can't find an example for guidance. I need to write a function that takes the first two angles and returns the third:</p>
  
  <pre><code>#include &lt;stdio.h&gt;
  
  **//add your new function here**
  
  int main(int argc, const char * argv[])
  {
      float angleA = 30.0;
      float angleB = 60.0;
      float angleC = remainingAngle(angleA, angleB);
      printf("The third angle is %.2f\n", angleC);
      return 0;
  }
  </code></pre>
  
  <p>Any ideas?</p>