How to print patterns in informatica?

Source- 10,A 20,P 20,Q 10,B 10,C 20,R 20,S Target- 10,A 10,A,B 10,A,B,C 20,P 20,P,Q 20,P,Q,R 20,P,Q,R,S #informatica #informaticascenarios #informaticainterviews