I'm trying to separate the "TID" in an array from these multiple arrays but I couldn't find the efficient solution.
I've the following type of arrays in one variable:
Array
(
    [0] => Array
        (
            [tid] => 168
        )
)
Array
(
    [0] => Array
        (
            [target_id] => 14
        )
    [1] => Array
        (
            [target_id] => 15
        )
    [2] => Array
        (
            [target_id] => 37
        )
)
Array
(
)
Array
(
    [0] => Array
        (
            [target_id] => 36
        )
)
Array
(
    [0] => Array
        (
            [target_id] => 14
        )
    [1] => Array
        (
            [target_id] => 15
        )
)
Array
(
    [0] => Array
        (
            [target_id] => 36
        )
)
Array
(
    [0] => Array
        (
            [tid] => 168
        )
    [1] => Array
        (
            [tid] => 167
        )
)
These values are in one variable and there can be unlimited arrays.
And Expected Output:
Array
(
    [0] => Array
        (
            [tid] => 168
        )
    [1] => Array
        (
            [tid] => 168
        )
    [2] => Array
        (
            [tid] => 167
        )
)