Then the solution is the following. We have to introduce extra variables y_ij for each arc ij. Then we have the two inequalities which amount to simply saying that y_ij must be greater than or equal to the absolute value of the difference. This means that the value must be more than 1 if the two values are different, or 0 if the values are equal. Then we may consider the following polyhedron where we have these inequalities together with the previous inequality for the hypercube. We want also to identify two specific nodes: one is the source and the other one is the sink, so that we define all possible cut-sets separating the source from the sink.