P1: (0, 0)
P2: (0.5, 18)
P3: (1.5, 6)
P4: (3, 12)
P5: (4, 12)
f = Segment(P1, P2)
g = Segment(P2, P3)
h = Segment(P3, P4)
i = Segment(P4, P5)