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

Difficulty: Very hard (0)

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

Difficulty: Very easy (0)

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

Difficulty: Very hard (0)

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

Difficulty: Super easy (0)