, b2, &quot;order&quot;, 2);</b>
<b class="fc">&nbsp;        a1.addEdge(&quot;ab&quot;, b3, &quot;order&quot;, 3);</b>
<b class="fc">&nbsp;        a1.addEdge(&quot;ab&quot;, b4, &quot;order&quot;, 0);</b>
<b class="fc">&nbsp;        a2.addEdge(&quot;ab&quot;, b1, &quot;order&quot;, 1);</b>
<b class="fc">&nbsp;        a2.addEdge(&quot;ab&quot;, b2, &quot;order&quot;, 2);</b>
<b class="fc">&nbsp;        a2.addEdge(&quot;ab&quot;, b3, &quot;order&quot;, 3);</b>
<b class="fc">&nbsp;        Vertex c1 = this.sqlg