title: problem in c there's an empty character constant error
body: <p>I've got a problem in C. The console says that there's an empty character constant. It's a little program to know how much books have a person. Here is the code :</p>
  <pre><code>int main ()
  {
      int nb_books;
      printf(&quot;How much books have you got?&quot;);
      scanf(&quot;%d&quot;,&amp;nb_books);
      printf(&quot;You have %d book%c!\n&quot;,nb_books, (nb_books==0||nb_books==1)?'':'s');
      return 0;
  }
  </code></pre>
  <p>The problem is with <code>%c</code>, I'd like to put a <code>s</code> when there are several books. That's all!</p>