How to detect duplicate?

[Anonymous]

Employee                Status                         StatusId

Alex                         Submit                             A1

Alex                         Submit                              A2

Alice                         In progress                        B1

Jack                         Submit                              C1

Jack                         In progress                        C2

What formula should i use,I want to show If employee has more than one status then it is duplicate and show the duplicate id.

The result should be:

Employee   Status                          Duplicate ID

Alex           Duplicate                         A1,A2

Jack           Duplicate                         C1,C2

TQ

[Anonymous]

Tq Jagan Mohan