C++ Institute CPA-21-02 問題集

質問 1：
What is the output of the program?
#include <iostream>
#include <string>
using namespace std;
int main()
{
string s1[]= {"Hello" , "World" };
for (int i=0; i<2; i++) {
cout << s1[i];
}
return( 0 );
}
A. It prints: HelloWorld
B. It prints: WorldHello
C. It prints: Hello
D. It prints: World
正解：A

質問 2：
What happens when you attempt to compile and run the following code?
#include <iostream>
using namespace std;
int main(){
int *i;
i = new int;
*i = 1.0 / 2 * 2 / 1 * 2 / 4 * 4;
cout << *i;
return 0;
}
A. It prints: 2
B. It prints: 0
C. It prints: 1
D. It prints: 0.5
正解：A

質問 3：
What happens when you attempt to compile and run the following code?
#include <iostream>
using namespace std;
int main()
{
int x,y=10;
float f;
f = 5.90;
cout << f << ", ";
x=f;
cout << x <<", ";
f=y;
cout << f;
return 0;
}
A. It prints: 5, 5, 10.00
B. It prints: 6, 5, 10
C. It prints: 6, 5, 10.00
D. It prints: 5.9, 5, 10
正解：D

質問 4：
What happens when you attempt to compile and run the following code?
#include <iostream>
using namespace std;
class A
{
public:
virtual void Print(){ cout<<"A";}
};
class B:public A
{
public:
void Print(){ cout<< "B";}
};
int main()
{
A *obj;
A ob1;
obj = &ob1;
obj?>Print();
B ob2;
obj = &ob2;
obj?>Print();
}
A. It prints: AA
B. It prints: BA
C. It prints: AB
D. It prints: BB
正解：C

質問 5：
What happens when you attempt to compile and run the following code?
#include <iostream>
using namespace std;
void fun(int*);
int main()
{
int *x;
int i=2;
x=&i;
fun(x);
cout<<i;
return 0;
}
void fun(int *i)
{
*i = *i * *i;
}
A. It prints: 4
B. It prints: 2
C. It prints: 0
D. It prints: 1
正解：A