Good evening.
I'm glad to welcome you on this Codeforces beta round.
Authors of today problemset are Ripatti (it is me) and Lepetrandr. it4.kp, MikeMirzayanov, RAD, Nerevar and dlevshunov helped in preparing the round. Delinur translated statements into English.
Good luck for all!
UPD
Winner is Neverauskas.
Editorial.
I'm glad to welcome you on this Codeforces beta round.
Authors of today problemset are Ripatti (it is me) and Lepetrandr. it4.kp, MikeMirzayanov, RAD, Nerevar and dlevshunov helped in preparing the round. Delinur translated statements into English.
Good luck for all!
UPD
Winner is Neverauskas.
Editorial.