6
	5	8
		9	1
					6	2
						7	1
					1

Difficulty: Very hard (0)

						7
						3		4
				3
6		5				8		7
				4
1		4
		9

Difficulty: Very hard (0)

		8
2	7
							8
			7			9		1
				7
1		5			7
	4
							1	4
						4

Difficulty: Super hard (42)

		1					4
			8
				1			6
								7
8
	4			3
					9
	3					1

Difficulty: Super hard (91)