Identify duplicates data

[Anonymous]

How to check duplicate values in a column1, create new  adde column, if in case duplicate values present in the column1 display as well new added column ...

With out grouping, Is there any alternativies to fing the duplicates ?like IF condition like this,,
ex: i have tried somthing in statically : if ([Column1] <> "null") then Table.RowCount(Table.SelectRows(#"Changed Type5", each ([Column1] = "Bike"))) else ""
but is there in any altenativies.....

Ex :

[AlienSx]

hi @Anonymous try this

lst = List.Buffer(List.RemoveNulls(prev_step[Column1])),
next_step = Table.AddColumn(prev_step, "cnt", (x) => if x[Column1] = null then "" else List.Count(List.PositionOf(lst, x[Column1], Occurrence.All)))

[Anonymous]

Thanks for the reply, But not working above Logic, Use only Power query Editor only.....