title: How can I predetermine the size of a malloc to concatenate an array of strings?
body: <blockquote>
  <p>Implement the append function that has the prototype below. The function returns a string that represents the concatenation of all the strings present in an array of strings. For this problem, you can assume the end of the parameter array is marked by <code>NULL</code>. You need to allocate memory for the resulting string.  You may not modify the array parameter.</p>
  <pre><code>char* append(char *data[]); 
  </code></pre>
  </blockquote>
  <p>I don't understand how to determine the size to <code>malloc</code> the pointer.</p>