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

Difficulty: Hard (0)

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

Difficulty: Very easy (0)

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

Difficulty: Easy (0)

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

Difficulty: Hard (0)