[[0 0 0 0],
 [5 8 0 0],
 [0 0 3 0],
 [0 6 0 0]]
	
[5, 8, 3, 6]
[0, 0, 2, 3, 4]
[0, 1, 2, 1,]
	
[[0 0 0 0],
 [5 8 0 0],
 [0 0 3 0],
 [0 6 0 0]]
	
[5, 8, 3, 6]
[0, 0, 2, 3, 4]
[0, 1, 2, 1,]
	
[[10 20 0 0 0 0],
 [0 30 0 40 0 0]
 [0 0 50 60 70 0]
 [0 0 0 0 0 80]]
	
[ 5 8 3 6 ]
[ 0 0 2 3 4 ]
[ 0 1 2 1 ]
	
[[0 0 0],
 [0 0 0],
 [0 0 0]]
	
[ ]
[ 0 0 0 0 ]
[ ]
	
[[1 1 1],
 [1 1 1],
 [1 1 1]]
	
[ 1 1 1 1 1 1 1 1 1 ]
[ 0 3 3 3 ]
[ 0 1 2 0 1 2 0 1 2 ]