689. Maximum Sum of 3 Non-Overlapping Subarrays (Hard)
Inagivenarraynumsofpositiveintegers,findthreenon-overlappingsubarrayswithmaximumsum.Eachsubarraywillbeofsizek,andwewanttomaximizethesumofall3*kentries.Returntheresultasalistofindicesrepresentingthesta