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1有如下程序：#include <iostream>using namespace std;class Base{public:Base(int x=0){cout<<x;}};class Derived:public Base{public:Derived(int x=0){cout<<x;}private:Base val;};int main(){Derived d(1);return 0;}程序的输出结果是
A.0
B.1
C.01
D.001
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2有如下程序：#include <iostream>using namespace std;class Part{public:Part(int x=0):val(x){cout<<val;}~Part(){cout<<val;}private:int val;};class Whole{public:Whole(int x,int y, int z=0):p2(x),p1(y),val(z){cout<<val;}~Whole(){cout<<val;}private:Part p1,p2;int val;};int main(){Whole obj(1,2,3);return 0;}程序的输出结果是
A.123321
B.213312
C.213
D.123123
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3有如下程序：#include <iostream>using namespace std;class MyClass{public:MyClass(int x):val(x){}void Print() const {cout<<"const:val="<<val<<'t';}void Print(){cout<<"val="<<val<<'t';}private:int val;};int main(){const MyClass obj1(10);MyClass obj2(20);obj1.Print();obj2.Print();return 0;}程序的输出结果是
A.val=10 const:val=20
B.const:val=10 const:val=20
C.const:val=10 val=20
D.val=10 val=20
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4有如下程序：#include <iostream>using namespace std;class MyClass{public:MyClass(){++count;}~MyClass(){--count;}static int getCount(){return count;}private:static int count;};int MyClass::count=0;int main(){MyClass obj;cout<<obj.getCount();MyClass *ptr=new MyClass;cout<<MyClass:getCount();delete ptr;cout<<MyClass::getCount();return 0;}程序的输出结果是
A.121
B.232
C.221
D.122
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5已知一程序运行后执行的第一个输出操作是cout<<setw(10)<<setfill('*')<<1234;此操作的输出结果是
A.1234
B.******1234
C.**********1234
D.1234******
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6有如下程序：#include <iostream>using namespace std;class Base{public:void output(){cout<<1;}virtual void Print(){cout<<'B';}};class derived:public Base{public:void output(){cout<<2;}void Print(){cout<<'D';}};int main(){Base *ptr=new Derived;ptr->output();ptr->Print();delete ptr;return 0;}程序的输出结果是
A.1B
B.1D
C.2B
D.2D
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7下列是重载惩罚运算符的函数原型生命，其中错误的是
A.MyClass operator *(double,double);
B.MyClass operator * (double,MyClass);
C.MyClass operator * (MyClass,double);
D.MyClass operator * (MyClass,MyClass);
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8如下函数的作用是以双倍行距输出文件：void double_space(ifstream& f,ofstream& t){char c;while (__________){____________;if(c=='n') t.out(c);}}画线处缺失的部分是
A.f.get(c)与t.put(c)
B.f.put(c)与t.get(c)
C.t.get(c)与f.put(c)
D.t.put(c)与f.get(c)
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9有如下程序：#include <iostream>using namespace std;class B{public:virtual void show(){cout<<"B";}};class D:public B{public:void show(){cout<<"D";}};void fun1(B *ptr){ptr->show();}void fun2(B &ref){ref.show();}void fun3(B b){b.show();}int main(){B b,*p=new D;D d;fun1(p);fun2(b);fun3(d);return 0;}程序的输出结果是
A.BBB
B.BBD
C.DBB
D.DBD
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