Array Union: Array
(
    [0] => 50
    [1] => 77
    [2] => 80
    [3] => 0
)
<br>Equality (==): bool(true)
<br>Identical (===): bool(true)
<br>Inequality (!=): bool(false)
<br>Inequality (<>): bool(false)
<br>Strict Inequality (!==): bool(false)