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

Difficulty: Easy (0)

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

Difficulty: Very easy (0)

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

Difficulty: Very hard (0)

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

Difficulty: Very easy (0)