Arrangeable graph

Arrangeable graph --- аранжируемый граф.

A cf-graphis called arrangeable if its arrangementexists and nonarrangeable otherwise.

Every arc of an arrangeable graph [math]\displaystyle{ G }[/math] is either forward or backward arc. An arc of [math]\displaystyle{ G }[/math] is called a backward arc if it is an [math]\displaystyle{ F }[/math]-inverse arcfor an arrangement of [math]\displaystyle{ G }[/math] and a forward arc if it is an [math]\displaystyle{ F }[/math]-direct arcfor an arrangement of [math]\displaystyle{ G }[/math].

A depth of an arrangeable graph [math]\displaystyle{ G }[/math] is defined as the depth of an arrangement of [math]\displaystyle{ G }[/math].