">&lt;&gt;</span> <span class="identifier">dis</span><span class="special">(-</span><span class="number">10</span><span class="special">,</span> <span class="number">10</span><span class="special">);</span>
  <span class="keyword">double</span> <span class="identifier">x1</span> <span class="special">=</span> <span class="identifier">dis</span><span class="special">(</span><span class="identifier">gen</span><span class="special">);</span>
  <span class="keyword">double</span> <span class="identifier">x2</sp