Hello
Consider the following content of a file:

     15,10,name3
     10,#,name1
     12,10,name2
     5,12,name4
     8,5,name4

[download]

Each line is in the following format:

     id,parent-id,name

[download]
Notice that the the great parent (the one without a parent) has # in the parent-id field.
I'm trying to create a new list which each line is a path from each id to its parent-id.
The expected output of the example I gave:

    name1
    name2,name1
    name3,name1
    name4,name2,name1
    name5,name4,name2,name1

[download]

I was trying to solve this issue with a loop and an array.
Problem is, I don't know how many fields should the array contain.
How can I solve this issue in the cleanest and simplest way possible, without using any external modules?
I feel like a loop over the file should solve it, but can't figure the right order.

In reply to Reorganizing the content of a file by ovedpo15

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