The goal is to convert a flat parent-child array into another flat array like this

Original Array
(
[0] => Array
(
[0] => categorycode
[1] => categoryname
[2] => parentcategorycode
)

[1] => Array
(
[0] => 1
[1] => Cavi
[2] => 0
)

[2] => Array
(
[0] => 2
[1] => Cavi Computer
[2] => 1
)

[3] => Array
(
[0] => 3
[1] => Cavi Seriali e Paralleli
[2] => 2
)

[4] => Array
(
[0] => 4
[1] => Ufficio
[2] => 0
)

[5] => Array
(
[0] => 5
[1] => Manutenzione
[2] => 4
)

[6] => Array
(
[0] => 6
[1] => Valigette attrezzi per reti
[2] => 5
)

[7] => Array
(
[0] => 7
[1] => Accessori
[2] => 0
)

[8] => Array
(
[0] => 8
[1] => Manutenzione
[2] => 7
)

[9] => Array
(
[0] => 9
[1] => Valigette attrezzi per reti
[2] => 8
)

[10] => Array
(
[0] => 10
[1] => Networking
[2] => 0
)

[11] => Array
(
[0] => 11
[1] => Componenti passivi
[2] => 10
)
.....

flat array as result

array(
[1] => Cavi
[2] => Cavi/Cavi Computer
[3] => Cavi/Cavi Computer/Cavi Seriali e Paralleli
[4] => Ufficio
[5] => Ufficio/Manutenzione
[6] => Ufficio/Manutenzione/Valigette attrezzi per reti
...
)