下面程序执行后的输出结果为( )。 public class fun { public static void main(String args[]) { String greets = " How are you!"; String s = greets.substring(0,3); System.out.println(s); } }
A.How
B.are
C.you
D.how are you!
第1题:
对于下面程序,对p进行赋值正确的是( )。 class A{ public:fun(int i){cout<<i<<endl;} }; main(){ void(A::*p)(int); }
A.p=fun;
B.p=fun();
C.p=A::fun;
D.p=A::fun()
第2题:
有如下程序: #include<iostream> using namespace std; class Base { public: void fun() { cout<<"Base::fun"<<endl; } }; class Derived: public Base { public: void tim() } ____________ cout<<"Derived:: fun"<<endl; } }; int main() { Derived d; d.fun(); return O; } 已知其执行后的输出结果为: Base::fun Derived::fun 则程序中下划线处应填入的语句是
A.Base.fun();
B.Base::fun();
C.Base->fun();
D.fun();
第3题:
在下面程序的横线处填上适当的内容,使程序执行后的输出结果为ABCD。
include<iostream>
using namespace std;
class A
{
public: A(){cout<<'A';}
};
class B:【 】
{
public:B(){cout<<'B';)
};
class C:【 】
{
public;C(){cout<<'C';}
};
class D:public B,public C
{
public:D(){cout<<'D';}
};
void main(){D obi;}
第4题:
在下面程序的横线处填上适当的内容,使程序执行后的输出结果为ABCD。
include <iostream.h>
using namespace std;
class A
{
public: A() {cout<<'A';
};
class B:______
{
public: B() {cout<<'B';}
};
class C:______
{
public: C(} cout<<'C';}
};
class D:public B, public C
{
public: D(){cout<<'D';}
};
void main(){D obj;}
第5题:
下面程序的结果是 ______。 #include<iostream.h> class A{ public: virtual void fun()=0{}; }; class B:public A{ public: void fun () {cout<< "new file" ;} }; class C: public A{ public: void fun (){cout<<"open file"<< " " } }; class D: public A{ public: void fun () {cout<< "save file\n" ;} }; void main() { A a,*p; B b; C c; D d; p=&c; p->fun (); p=&b; p->fun (); p=&d; p->fun(); }
A.new file open file save file
B.new file new file new file
C.编译出错
D.open file new file save file
第6题: