[LeetCode 358] Rearrange String k Distance aPart (Hard**)
Givenanon-emptystringsandanintegerk,rearrangethestringsuchthatthesamecharactersareatleastdistancekfromeachother.Allinputstringsaregiveninlowercaseletters.Ifitisnotpossibletorearrangethestring,returnan