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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)

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

Difficulty: Very easy (0)

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

Difficulty: Very easy (0)