p0:PNPlace
p1:PNPlace
p2:PNPlace
p3:PNPlace
p4:PNPlace

t0:PNTransition
:arc (p0 -> t0)
:arc (t0 -> p1)

t1:PNTransition
:arc (p1 -> t1)
:arc (t1 -> p2)

t2:PNTransition
:arc (p2 -> t2)
:arc (t2 -> p0)


t3:PNTransition
:arc (t3 -> p4)