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

Difficulty: Easy (0)

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

Difficulty: Super easy (0)

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

Difficulty: Hard (0)

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

Difficulty: Very easy (0)