anchor.diff:                    (無し)
                   <% else %>
                    <%= event.users.count %>名
  -                 <% end %>
  +                <% end %>
                 </td>
                 <td><%= event.formatted_date.blank? ? '(未入力)' : event.formatted_date %></td>
               </tr>
  
positive.code:         <div class="well bs-component">
            <table class="table table-borderd">
              <tr>
                  <th>詳細</th>
                  <th>ID</th>
                  <th>イベント名</th>
                  <th>概要</th>
                  <th>参加者</th>
                  <th>開催日</th>
              </tr>
              <% @events.each do |event|%>
              <tr>
  
negative.code:     <div class="row">
        <div class="col-lg-8 col-lg-offset-2">
          <div class="well bs-component">
            <%= link_to 'イベントを作るよ', {controller: :events, action: :new}, class: :"btn btn-success btn-lg" %>
            <%= link_to '戻る', :root, class: :"btn btn-default btn-lg" %>
          </div>
        </div>
      </div>
  