4						7	6	8
1
	7				5
		9		8		3	4
5								9
	3	4		5		8
			2				8
								3
6	4	5						7

Difficulty: Easy (0)

	4		2		6	9
	2							1
		9				5	6
					2		5
4			1		5			8
	6		9
	5	1				3
2							1
		3	6		1		7

Difficulty: Super easy (0)

						6	9
		5					2	4
					4	3	5
	3	4					1
		6				7
	2					4	3
	1	9	6
2	5					9
	7	3

Difficulty: Very easy (0)

1			8	6			4
				1		9
	7						6
						3		2
9			1		2			4
7		2
	9						3
		1		3
	4			2	6			9

Difficulty: Easy (0)