Error Handling(C++ Programming ) Questions and answers for exam Preparation

Question 1.

Which exception is thrown by dynamic_cast?

bad_cast
bad_typeid
bad_exception
bad_alloc

Explanation:-

Answer: Option A. -> bad_cast

bad_cast exception is thrown by dynamic_cast.

Question 2.

How do define the user-defined exceptions?

inheriting and overriding exception class functionality.
overriding class functioality.
inheriting class functionality
none of the mentioned

Explanation:-

Answer: Option A. -> inheriting and overriding exception class functionality.

None.

Question 3.

What is the output of this program?

1.
#include
2.
#include
3.
using namespace std;
4.
struct MyException : public exception
5.
{
6.
const char * what () const throw ()
7.
{
8.
return "C++ Exception";
9.
}
10.
};
11.
int main()
12.
{
13.
try
14.
{
15.
throw MyException();
16.
}
17.
catch(MyException& e)
18.
{
19.
cout

C++ Exception
Exception caught
Exception caught C++ Exception
error

Explanation:-

Answer: Option C. -> Exception caught C++ Exception

We are defining the user-defined exception in this program.
Output:
$ g++ excep4.cpp
$ a.out
C++ Exception
Exception caught

Question 4.

What is the output of this program?

1.
#include
2.
#include
3.
using namespace std;
4.
int main ()
5.
{
6.
try
7.
{
8.
int* myarray = new int[1000];
9.
cout

allocated
Standard exception
Depends on the memory
error

Explanation:-

Answer: Option C. -> Depends on the memory

In this program, We are allocating the memory for array. If it is allocated means, no exception

will arise and if there is no size in memory means, Exception will arise.
Output:
$ g++ excep3.cpp
$ a.out
allocated

Question 5.

What is the output of this program?

1.
#include
2.
#include
3.
using namespace std;
4.
class myexception: public exception
5.
{
6.
virtual const char* what() const throw()
7.
{
8.
return "My exception";
9.
}
10.
} myex;
11.
int main ()
12.
{
13.
try
14.
{
15.
throw myex;
16.
}
17.
catch (exception& e)
18.
{
19.
cout

exception
error
My exception
runtime error

Explanation:-

Answer: Option C. -> My exception

This is a standard exception handler used in the class.
Output:
$ g++ excep2.cpp
$ a.out
My exception

Question 6.

What is the output of this program?

1.
#include
2.
using namespace std;
3.
int main ()
4.
{
5.
try
6.
{
7.
throw 20;
8.
}
9.
catch (int e)
10.
{
11.
cout

20
An exception occurred
error
An exception occurred 20

Explanation:-

Answer: Option D. -> An exception occurred 20

We are handling the exception by throwing that number. So the output is printed with the given number.
Output:
$ g++ excep1.cpp
$ a.out
An exception occurred 20

Question 7.

What is the output of this program?

1.
#include
2.
using namespace std;
3.
double division(int a, int b)
4.
{
5.
if (b == 0)
6.
{
7.
throw "Division by zero condition!";
8.
}
9.
return (a / b);
10.
}
11.
int main ()
12.
{
13.
int x = 50;
14.
int y = 0;
15.
double z = 0;
16.
try
17.
{
18.
z = division(x, y);
19.
cout

50
0
Division by zero condition!
error

Explanation:-

Answer: Option C. -> Division by zero condition!

It's a mathematical certainty, We can't divide by zero, So we're arising a exception.
Output:
$ g++ excep.cpp
$ a.out
Division by zero condition!

Question 8.

Which is used to throw a exception?

throw
try
catch
none of the mentioned

Explanation:-

Answer: Option A. -> throw

None.

Question 9.

What is the use of the 'finally' keyword?

It used to execute at the starting of the program
It will be executed at the end of the program even if the exception arised.
Both a & b
none of the mentioned

Explanation:-

Answer: Option B. -> It will be executed at the end of the program even if the exception arised.

finally keyword will be executed at the end of all the exception.

Question 10.

Which keyword is used to handle the expection?

try
throw
catch
none of the mentioned

Explanation:-

Answer: Option C. -> catch

When we found a exception in the program, We need to throw that and we handle that by using