<span class="r-pr">#&gt;</span> {2, (1L 2L), 1}</span>
<span class="r-in"><span></span></span>
<span class="r-in"><span><span class="va">s1</span> <span class="op">-</span> <span class="va">s2</span></span></span>
<span class="r-out co"><span class="r-pr">#&gt;</span> {1}</span>
<span class="r-in"><span><span class="va">s2</span> <span class="op">-</span> <span class="va">s1</span></span></span>
<span class="r-out co"><span class="r-pr">#&gt;</span> {2}</span>
<span class="r-in"><span></span></span>
<span c