【单选题】关于下列 代码{empty param.user?"Administrator":param.user}说法正确的是( )
B.
如果参数user为空则返回Administrator否则就返回user的值
C.
如果参数user为空字符则返回Administrator否则就返回user的值
D.
如果参数user为空则返回user否则就返回Administrator的值
【单选题】已知有如下代码: import java.util.*; public class Test{ public static void main(String... args){ List list=new LinkedList(); list.offer("hello"); list.offer("welcome"); System.out.println(list); } } 关于下列代码说法正...
A.
编译失败,因为list是一个列表不是队列,无法调用offer方法
B.
编译成功,运行成功,因为list.offer("hello");根据多态性,绑定为LinkedList对象的offer方法
C.
编译成功,运行失败,根据动态性,list无法调用LinkedList的offer方法
【单选题】The circuit shown will have identical logic out if all gates are changed to
【单选题】The two types of gates which are called universal gates are
【单选题】All Boolean expressions can be implemented with ( )
C.
combinations of NAND and NOR gates
D.
combinations of AND gates, OR gates, and inverters
【单选题】Which form of logic gate system is given by a ladder diagram with a rung having two normally closed gates in series?