[]
0
[0, 1, 2, 3]
[10, 11, 12, 13]
4
[10, 11, 12]
[10, 11, 12, 13, 100]
[10, 11, 12]
[3, 4, 5, 6]
[2, 3]
[]
[]
[3, 4]
[4, 3, 2, 1]
[]
[3, 2, 1]
[2, 4]
[2, 4]
[1, 3, 5]
[3, 4]
[]
[1, 2, 3, 4]