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

Difficulty: Medium

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

Difficulty: Medium

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

Difficulty: Medium

6						7		1
4	6		5
			2
				3
			4
	1
	2						7
				3	5

Difficulty: Medium