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

Difficulty: Super easy (0)

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

Difficulty: Easy (0)

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

Difficulty: Super easy (0)

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

Difficulty: Very easy (0)