ent">%                    u(j) &lt;= u(i) + g_i^T(a_j - a_i), for all i,j</span>
<span class="comment">%                    u(i) &gt;= u(j), for all (i,j) in Pweak</span>
<span class="comment">%</span>
<span class="comment">% If the second LP has a strictly negative solution, we can deduce that</span>
<span class="comment">% u(k) &lt; u(0). If on the other hand the second LP has a nonnegative</span>
<span class="comment">% solution and the first LP has a strictly positive solution, we can</span>
<span class