阅读下列程序段,不合法的行是______。 class Computer{} class Monitor extends Computer{} class HardDrive extends Computer {public void test(){ Monitor a = new Monitor(); Computer b = new Monitor(); HardDrive c = (Hard
单选题
阅读下列程序段,不合法的行是______。 class Computer{} class Monitor extends Computer{} class HardDrive extends Computer {public void test(){ Monitor a = new Monitor(); Computer b = new Monitor(); HardDrive c = (Hard