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

Difficulty: Very easy (0)

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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)

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

Difficulty: Very easy (0)