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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)

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

Difficulty: Super easy (0)

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

Difficulty: Medium (0)