Filter a Column by Another Columns Value (Grouped)

I have Column A (QuoteNo) and column B (QuoteSubNo). There can be many QuoteSubNo values to 1 QuoteNo, but I just want to see the latest.

So, how do I filter QuoteSubNo on the highest number, based on a grouping of QuoteNo.

A B
1 1
1 2
1 3
2 1
2 2
2 3
2 4

So here I would just want to see QuoteSubNo's 3, 3, 4.

Thanks in advance.

I've found a way. Here's what I've done in-case anyone else has the same problem:

Sorted the columns by:
A (QuoteNo) Desc
B (QuoteSubNo) Asc

In a blank column (C) I added a VLookup formula to match the QuoteNo and return the QuoteSubNo. Because VLookup works top to bottom it always returns the highest QuoteSubNo - because of the sort earlier.

In another blank column (D) I added a simple boolean formula to tell me whether the VLookup result matches the QuoteSubNo. Example, in cell D2 I put "=C2=B2".

Finally filter column D to show only TRUE.