Array
(
    [0] => Array
        (
            [0] => 1
            [1] => 3
            [2] => 5
        )

    [1] => Array
        (
            [x1] => 2
            [x2] => 4
        )

)
Array
(
    [0] => Array
        (
            [0] => 1
            [1] => 3
            [2] => 5
        )

    [1] => Array
        (
            [x1] => 2
            [x2] => 4
        )

)