How to send Unique (Distinct) records into One target and duplicates into another target?

Source:

Ename	EmpNo
stev	100
Stev	100
john	101
Mathew	102

Output:

Target_1:

Ename	EmpNo
Stev	100
John	101
Mathew	102

Target_2:

Ename	EmpNo
Stev	100

Approch 1: Using Dynamic Lookup on Target table:

If record doen’t exit do insert in target_1 .If it is already exist then send it to Target_2 using Router.

Approch2: Using Var port :

Sort the data in sq  based on EmpNo column then Use expression to store previous record information using Var ports after that use router to route the data into targets  if it is first time then sent it to first target  if it is already inserted then send it to Tartget_2.