Oleg client Igor analyst good friend however argue little thing recently start new company have trouble find companyto settle problem they ve decide play game the company consist n letter Oleg Igor set n letter contain multiple copy letter set different Initially company denote n question mark Oleg Igor take turn play game Oleg move in turn player choose letter c set replace question mark c then copy letter c remove set the game end question mark replace letterFor example suppose Oleg set letter ioi Igor set letter imo one possible game follow Initially company Oleg replace second question mark the company the set letter Oleg ioigor replace question mark o the company io the set letter Igor imFinally Oleg replace question mark o the company oio the set letter Oleg iin end company oioOleg want company lexicographically small possible Igor want company lexicographically large possible what company Oleg Igor play optimallya string ss1s2sm call lexicographically small string tt1t2tm st siti small index siti sjtj ji