7									4
5		3	4			11	10				1
		2		7			3	11			10
		8						2			12
		7	6		1	10	8		9
		11	2							10
	12							9	1
		1		6	8	7		12	2
4			8						10
2			3	11			4		5
10				8	3			1	11		6
	1									12

Difficulty: Easy (0)

		12		2		9		5
	6									4	7
	2			6				9			1
2						5
	8	10	5		12			6
7					1	11	6	8		3
	12		10	9	2	7					6
			9			6		4	8	7
					5						11
1			11				8			5
12	9									10
			3		11		1		6

Difficulty: Hard (0)

									9	5	10
		5	4		6	9		11
		1	11						2	8
7			10			11	4	5			12
				12		2				6
	11	2	12		3	10			4
		7			9	3		2	6	10
	5				1		11
3			9	2	10			12			1
	9	10						6	5
			8		11	5		7	10
2	4	11

Difficulty: Easy (0)

5			7		4					11	10
8				3	6				4	12
	4		2						7
7	1			8	12		4	3
	5		4	10
10	3	2			9	7
					11	1			3	4	8
							10	9		7
			3	7		6	8			2	11
		7						2		5
	2	12				3	5				7
1	11					2		4			12

Difficulty: Very easy (0)