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

Difficulty: Super easy (0)

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

Difficulty: Very easy (0)

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

Difficulty: Super easy (0)

	4			8
		1
9
					1
			2				9
	2	4		3		7
	7			4
		3

Difficulty: Very hard (0)