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

Difficulty: Very easy (0)

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

Difficulty: Very hard (0)

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

Difficulty: Very easy (0)

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

Difficulty: Very easy (0)