[[1, 3, 5], [20, 20, 20], [7, 8, 9]]
[[1, 3, 5], [2, 4, 6], [20, 20, 20]]
[[1, 3, 5], [20, 4, 6], [7, 8, 9]]
[[1, 3, 5], [2, 4, 6], [7, 20, 9]]