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

Difficulty: Very easy (0)

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

Difficulty: Hard (0)

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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)