[1, 0, 0, 0, 0]
[1, 0, 0, 2, 0]
[1, 0, 3, 2, 0]
[4, 1, 3, 2, 0]
[4, 1, 3, 2, 0]
[4, 1, 3, 2, 5]
4 1 3 2 5