1		8				7			5
			7					1
			6						2
7				2	5		4		8
		9					1		4
3		4					10
8		10		9	7				6
4						10
	3					5
2			5				7		3

Difficulty: Very easy (0)

3		7			10			9
9	5							2	10
10			8
							7
		9			2		4
		5		1			3
		3
						7			5
7	10							6	2
	3			5			9		4

Difficulty: Hard (0)

5					8	9			10
	6						10	4
7			3		4
			1			7
	8	4	10	6	9
				3	10	6	1	9
			9			4
				4		10			3
	1	2						7
10			4	8					5

Difficulty: Very easy (0)

		10		1					3
		5		6		9			2
			3		4
	1		2	10					5
	3		7
						6		1
10					7	8		3
				3		4
8			9		6		1
7					3		4

Difficulty: Very easy (0)