pan class="mf">1.</span><span class="o">-</span><span class="n">prob</span><span class="p">)</span><span class="o">/</span><span class="mf">2.</span><span class="p">,</span> <span class="p">(</span><span class="mf">1.</span><span class="o">-</span><span class="n">prob</span><span class="p">)</span><span class="o">/</span><span class="mf">2.</span><span class="p">])</span>

    <span class="nb">print</span><span class="p">(</span><span class="s1">&#39;start&#39;</span><span class="p">)</span>
    <span class