Array sort

Before sort

Array
(
    [1] => H
    [2] => t
    [3] => O
    [4] => 9
    [5] => P
    [6] => k
    [7] => L
    [8] => o
    [9] => s
)

After sort

Array
(
    [0] => 9
    [1] => H
    [2] => L
    [3] => O
    [4] => P
    [5] => k
    [6] => o
    [7] => s
    [8] => t
)