The initial array

Array
(
    [zero] => 0
    [one] => 1
)

Passing arrays into functions

Array
(
    [zero] => 0
    [one] => 1
)

Array
(
    [zero] => 2
    [one] => 1
)

Passing arrays into foreach loops

Array
(
    [zero] => 2
    [one] => 1
)

Array
(
    [zero] => 5
    [one] => 5
)

Passing arrays into the assignment operator

Array
(
    [zero] => 5
    [one] => 5
)

Array
(
    [zero] => 100
    [one] => 5
)

Returning arrays from functions

Array
(
    [zero] => 100
    [one] => 5
)

Array
(
    [zero] => 3
    [one] => 5
)