Declaration C++ MCQ

1. Choose the correct option.
    extern int i;
    int i;
a) both 1 and 2 declare i
b) 1 declares the variable i and 2 defines i
c) 1 declares and defines i, 2 declares i
d) 1 declares i,2 declares and defines i

Answer:d

2. Pick the right option
    Statement 1:A definition is also a declaration.
    Statement 2:An identifier can be declared just once.
a) Statement 1 is true, Statement 2 is false.
b) Statement 2 is true, Statement 1 is false.
c) Both are false.
d) Both are true.

Answer: b

3. Which of the given statements are false.
1. extern int func;
2. extern int func2(int,int);
3. int func2(int,int);
4. extern class foo;
a) 3 and 4 only
b) 2 and 3 only
c) only 4
d) 2, 3 and 4

Answer:c

4. Pick the right option
    Statement 1:Global values are not initialized by the stream.
    Statement 2:Local values are implicitly initialised to 0.
a) Statement 1 is true, Statement 2 is false.
b) Statement 2 is true, Statement 1 is false.
c) Both are false.
d) Both are true.

Answer:c

5. What is the output of this program?

1.     #include <iostream>

2.     using namespace std;

3.     int g = 100;

4.     int main()

5.     {

6.         int a;

7.         {

8.             int b;

9.             b = 20;

10.             a = 35;

11.             g = 65;

12.            cout << b << a << g;

13.         }

14.         a = 50;

15.         cout << a << g;

16.         return 0;

17.     }

a) 2035655065
b) 2035655035
c) 2035635065
d) none of the mentioned

Answer:a

6. Can two functions declare variables(non static) with the same name.
a) No
b) Yes
c) Yes, but not a very efficient way to write programs.
d) No, it gives a runtime error.

Answer:c

7. What is the output of this program?

1.     #include <iostream>

2.     using namespace std;

3.     void addprint()

4.     {

5.         static int s = 1;

6.         s++;

7.         cout << s;

8.     }

9.     int main()

10.     {

11.         addprint();

12.         addprint();

13.         addprint();

14.         return 0;

15.     }

a) 234
b) 111
c) 123
d) 235

Answer:a

8. What is the output of this program?

1.     #include <iostream>

2.     using namespace std;

3.     int main()

4.     {

5.         int a = 10;

6.         if (a < 10) {

7.             for (i = 0; i < 10; i++)

8.                cout << i;

9.         }

10.         else {

11.             cout << i;

12.         }

13.         return 0;

14.     }

a) 0123456789
b) 123456789
c) 0
d) error

Answer:d

9. Identify the incorrect statements.
    int var = 10;
    int *ptr = &(var + 1); //statement 1
    int *ptr2 = &var; //statement 2
    &var = 40; //statement 3
a) Statement 1 and 2 are wrong
b) Statement 2 and 3 are wrong
c) Statement 1 and 3 are wrong
d) All the three are wrong

Answer:c

10. Identify the type of the variables.
    typedef char* CHAR;
    CHAR p,q;
a) char*
b) char
c) CHAR
d) unknown

Answer:a