I need your help, I would like to retrieve the value of the column where the cell contains 1 here is an example:

Image

![](https://i.stack.imgur.com/P89jS.png)

A | B | C | D
-------------

1 | 0 | 0 |
-----------

0 | 1 | 1 |
-----------

1 | 1 | 0 |
-----------

The desired result:

A | B | C | D
-------------

1 | 0 | 0 | A
-------------

0 | 1 | 1 | B,C
---------------

1 | 1 | 0 | A,B
---------------

Thank you !