C++ Institute CPA 問題集

質問 1：
Which code, inserted at line 8, generates the output "0102020"?
#include <iostream>
using namespace std;
class Base {
static int age;
public:
Base () {};
~Base () {};
//insert code here
void Print() { cout << age;}
};
int Base::age=0;
int main () {
Base a,*b;
b = new Base();
a.Print();
a.setAge(10);
a.Print();
b->setAge();
a.Print();
b->Print();
return 0;
}
A. void setAge(int a) {age = a;}
B. void setAge() {age = 10;}
C. void setAge() {age = 20;}
D. void setAge(int a=20) {age = a;}
正解：D

質問 2：
If there is one, point out an error in the program
#include <iostream>
using namespace std;
int main()
{
int i=1;
for(;;)
{
cout<<i++;
if(i>5)
break;
}
return 0;
}
A. No error
B. Error in "if" statement
C. Error in "for" loop
D. Error in break statement
正解：A

質問 3：
What happens when you attempt to compile and run the following code?
#include <iostream>
using namespace std;
class complex{
double re;
double im;
public:
complex() : re(0),im(0) {}
complex(double x) { re=x,im=x;};
complex(double x,double y) { re=x,im=y;}
void print() { cout << re << " " << im;}
};
int main(){
complex c1;
double i=2;
c1 = i; c1.print(); return 0; }
A. It prints: 2 0
B. It prints: 2 2
C. It prints: 0 0
D. It prints: 1 1
正解：B

質問 4：
What happens when you attempt to compile and run the following code?
#include <iostream>
using namespace std;
int op(int x, int y)
{
return x?y;
}
int op(int x, float y)
{
return x+y;
}
int main()
{
int i=1, j=2, k, l;
float f=0.23;
k = op(i, j);
l = op(j, f);
cout<< k << "," << l;
return 0;
}
A. It prints: ?1,3
B. Compilation fails
C. It prints: ?1,?1
D. It prints: ?1,2
正解：D

質問 5：
What happens when you attempt to compile and run the following code?
#include <iostream>
using namespace std;
int op(int x, int y);
int main()
{
float *pf;
float f=0.9;
pf=&f;
cout << op(1, *pf);
return 0;
}
int op(int x, int y)
{
return x*y; }
A. It prints: 0
B. It prints: 1
C. It prints: 0.5
D. It prints: ?1
正解：A

質問 6：
Which of the following structures are correct?
1:
struct s1{ int x; char c;
};
2:
struct s2{ float f; struct s2 *s;
};
3:
struct s3{ float f; in i;
}
A. 2
B. 3
C. All of these
D. 1
正解：A,D

質問 7：
How many times will the program print "HELLO" ?
#include <iostream>
using namespace std;
int main()
{
cout<<"HELLO";
main();
return 0;
}
A. Till stack overflows
B. 65536
C. 32769
D. 1
正解：A

質問 8：
Which code, inserted at line 5, generates the output "ABC"?
#include <iostream>
using namespace std;
class A {
public:
//insert code here
};
class B:public A {
public:
void Print(){ cout<< "B"; }
};
class C:public B {
public:
void Print(){ cout<< "C"; }
};
int main()
{
A ob1;
B ob2;
C ob3;
A *obj;
obj = &ob1;
obj->Print();
obj = &ob2;
obj->Print();
obj = &ob3;
obj->Print();
}
A. virtual void Print(string s){ cout<<s;}
B. None of these
C. virtual void Print(){ cout<<"A";}
D. void Print(){ cout<<"A";}
正解：C