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

Difficulty: Super easy (0)

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

Difficulty: Super easy (0)

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

Difficulty: Super easy (0)

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

Difficulty: Very easy (0)