Find Min length of levels per group in flattened hierarchy

[OJet]

Hi Guys, 

I am working with a hierarchy. I flattened it so that columns 1-11 in the example below represent the  hierarchy path depth for  each item. Below is a small sample of the data (for the first item with ID 188- parent is item 186, grand- parent item 6, etc)

I am stuck with being able to identify the shortest depth per Some Grouping Column.  Column 'Min Length' is what I need to get. Would you be able to help?

SOME GROUPING	Item ID	1	2	3	4	5	6	7	8	9	10	11	Min Length
A	188	1	6	186	188								3
A	23	1	6	23									3
A	263	1	6	260	263								3
A	921	1	6	447	916	917	918	920	921				3
A	266	1	6	260	265	266							3
A	919	1	6	447	916	917	918	919					3
A	1025	1	6	447	1,024	1,025							3
A	165	1	6	23	74	164	165						3
A	1004	1	6	447	916	917	918	1,003	1,004				3
A	488	1	6	447	448								3
B	494	1	6	447	450	489	490	493	494				8
B	964	1	6	447	916	917	918	946	958	961	963	964	8
B	926	1	6	447	916	917	918	946	926				8
C	756	1	6	447	525	528	737	756					7
D	304	1	6	280	301	302	303	304					5
D	284	1	6	280	282	284							5
D	319	1	6	280	301	302	314	318	319				5

Thank you!

[Qiu · Accepted solution]

@OJet 
Hope this is what you need.

[OJet]

 Thank you so much, exactly what I needed!

[Qiu]

@OJet 
Glad to help and thank you for the accept mark also