PHP remove values from a single array? [duplicate]

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Possi开发者_开发知识库ble Duplicate:

How to remove duplicate values from an array in PHP

How can I remove all multiple values for example 55,55 will only be 55 using PHP

Example 1

Array
(
    [0] => 9
    [1] => 2
    [2] => 55
    [3] => 55
    [4] => 9
)

Example 1 should look like example 2 below.

Array
(
    [0] => 9
    [1] => 2
    [2] => 55
)

---

Use array_unique:

$a2 = array_unique($a);