          class="n">i</span><span class="p">[</span><span class="mi">1</span><span class="p">][</span><span
            class="mi">2</span><span class="p">],</span> <span class="n">t1</span><span class="o">=</span><span
            class="n">i</span><span class="p">[</span><span class="mi">0</span><span class="p">])</span>
                    <span class="n">set_edge</span><span class="o">.</span><span class="n">add</span><span
            class="p">((</span><span class="n">k</span><span class="p">,</span> 