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

Difficulty: Easy (0)

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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)

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

Difficulty: Hard (0)