ntifier">polygon_traits</span><span class="special">&lt;</span><span class="identifier">polygon</span><span class="special">&gt;::</span><span class="identifier">point_type</span> <span class="identifier">point</span><span class="special">;</span>

    <span class="identifier">point</span> <span class="identifier">pts</span><span class="special">[</span><span class="number">5</span><span class="special">]</span> <span class="special">=</span> <span class="special">{</span>
        <span class="identifier">b