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

Difficulty: Medium (0)

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

Difficulty: Very easy (0)

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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)