title: carousel is not show first picture
body: <p>I have written the following code for carousel, but it's not showing my first picture. Is my code right or am I missing something?</p>
  
  <pre><code>&lt;div id="myCarousel" class="carousel slide" data-ride="carousel"&gt;
      &lt;!-- Indicators --&gt;
      &lt;ol class="carousel-indicators"&gt;
         &lt;% @post.each_with_index do |photo,n| %&gt;
         &lt;li data-target='#myCarousel' data-slide-to="#{n}" class="#{'active' if n==0}"&gt;&lt;/li&gt;
         &lt;% end %&gt;
      &lt;/ol&gt;
      &lt;!-- Wrapper for slides --&gt;
      &lt;div class="carousel-inner" role="listbox"&gt;
          &lt;div class="item active"&gt;
              &lt;% if Post.first==nil %&gt;
                  &lt;img src="http://hometelvietnam.com/wp-content/uploads/2016/12/a614f72d-c487-438a-a16f-514e65406ed2.jpg" &gt;
                  &lt;div class="slider"&gt;
                  &lt;button class="btn btn-danger"&gt;&lt;h1 style="margin:5px; shadow: 0px 0px 0px 5 black;"&gt;Become a host now&lt;/h1&gt;&lt;/button&gt;
                  &lt;/div&gt;
              &lt;%else%&gt;
              &lt;% image_tag Post.first.post_picture %&gt;
              &lt;%end%&gt;
          &lt;/div&gt;
          &lt;% @post.drop(1).each do |photo| %&gt;
          &lt;div class="item"&gt;
              &lt;%= link_to (image_tag photo.post_picture),photo %&gt;
          &lt;/div&gt;
          &lt;%end%&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>