單項(xiàng)選擇題
A."Hello"(0),"Hello"(5) B."Hello".take(1),"Hello".reverse(0) C."Hello"(1),"Hello"(5) D."Hello".take(0), "Hello".takeRight(1)
A.import scala.math._ B.import sqrt C.import math._ D.import math.sqrt
A.1 B.2 C.3 D.4