Created A Nested Array Help

[drmovi]

Hi every body

I want to create an array which have the following roles

1- nested array with 4 level depth

2- each parent have only 2 children

3- if parent is P and 2children is C1 and C2 then :

C1 = P *2

C2 = P*2 + 1

 

for example array like this

array(

10=>array(

20=>array(

40=>array(

80,81)

,41=>array(82,83)),

21=>array(42))))

 

how could i code it using function with input id

eg: function createArray($id){}