n class="special">:</span>     <span class="identifier">interval</span> <span class="identifier">containers</span><span class="special">:</span>
<span class="identifier">T</span><span class="special">\</span><span class="identifier">P</span><span class="special">|</span> <span class="identifier">s</span> <span class="identifier">m</span>                <span class="identifier">T</span><span class="special">\</span><span class="identifier">P</span><span class="special">|</span> <span class="identifier">S1</s