A.mapPartitions B.lookup C.mapPartitionsWithIndex D.count
A.寬依賴 B.窄依賴 C.分區(qū)關(guān)系 D.繼承關(guān)系
A."Hello"(0),"Hello"(5) B."Hello".take(1),"Hello".reverse(0) C."Hello"(1),"Hello"(5) D."Hello".take(0), "Hello".takeRight(1)