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

Difficulty: Very easy (0)

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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)

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

Difficulty: Very easy (0)