size 6

initial:
(0,0)=4
(1,3)=5
(2,1)=5
(4,4)=5
(5,2)=4

constraints:
(0,0)>(0,1)
(0,2)>(0,3)

(1,0)<(1,1)
(1,3)>(1,4)

(2,0)>(2,1)
(2,2)<(2,3)

(3,1)<(3,2)

(4,1)>(4,2)
(4,3)<(4,4)

(5,3)>(5,4)