C Programming Questions and Answers on Basics of Functions for Freshers

1. What is the output of this C code?

1.     #include 

2.     int main()

3.     {

4.         void foo();

5.         printf("1 ");

6.         foo();

7.     }

8.     void foo()

9.     {

10.         printf("2 ");

11.     }

a) 1 2
b) Compile time error
c) 1 2 1 2
d) Depends on the compiler

Answer: a

2. What is the output of this C code?

1.     #include 

2.     int main()

3.     {

4.         void foo(), f();

5.         f();

6.     }

7.     void foo()

8.     {

9.         printf("2 ");

10.     }

11.     void f()

12.     {

13.         printf("1 ");

14.         foo();

15.     }

a) Compile time error as foo is local to main
b) 1 2
c) 2 1
d) Compile time error due to declaration of functions inside main

Answer: b

3. What is the output of this C code?

1.     #include 

2.     int main()

3.     {

4.         void foo();

5.         void f()

6.         {

7.             foo();

8.         }

9.         f();

10.     }

11.     void foo()

12.     {

13.         printf("2 ");

14.     }

a) 2 2
b) 2
c) Compile time error
d) Depends on the compiler

Answer: d

Explanation: Even though the answer is 2, this code will compile fine only with gcc. GNU C supports nesting of functions in C as a language extension where as standard C compiler doesn’t.

4. What is the output of this C code?

1.     #include 

2.     void foo();

3.     int main()

4.     {

5.         void foo();

6.         foo();

7.         return 0;

8.     }

9.     void foo()

10.     {

11.         printf("2 ");

12.     }

a) Compile time error
b) 2
c) Depends on the compiler
d) Depends on the standard

Answer: b

5. What is the output of this C code?

1.     #include 

2.     void foo();

3.     int main()

4.     {

5.         void foo(int);

6.         foo(1);

7.         return 0;

8.     }

9.     void foo(int i)

10.     {

11.         printf("2 ");

12.     }

a) 2
b) Compile time error
c) Depends on the compiler
d) Depends on the standard

Answer: a

6. What is the output of this C code?

1.     #include 

2.     void foo();

3.     int main()

4.     {

5.         void foo(int);

6.         foo();

7.         return 0;

8.     }

9.     void foo()

10.     {

11.         printf("2 ");

12.     }

a) 2
b) Compile time error
c) Depends on the compiler
d) Depends on the standard

Answer: b

7. What is the output of this C code?

1.     include <stdio.h>

2.     void m()

3.     {

4.         printf("hi");

5.     }

6.     void main()

7.     {

8.         m();

9.     }

a) hi
b) Run time error
c) Nothing
d) Varies

Answer: a

8. What is the output of this C code?

1.     #include 

2.     void m();

3.     void n()

4.     {

5.         m();

6.     }

7.     void main()

8.     {

9.         void m()

10.         {

11.             printf("hi");

12.         }

13.     }

a) hi
b) Compile time error
c) Nothing
d) Varies

Answer: b

9. What is the output of this C code?

1.     #include 

2.     void main()

3.     {

4.         m();

5.         void m()

6.         {

7.             printf("hi");

8.         }

9.     }

a) hi
b) Compile time error
c) Nothing
d) Varies

Answer: b

10. What is the output of this C code?

1.     #include 

2.     void main()

3.     {

4.         m();

5.     }

6.     void m()

7.     {

8.         printf("hi");

9.         m();

10.     }

a) Compile time error
b) hi
c) Infinite hi
d) Nothing

Answer: c

11. What is the output of this C code?

1.     #include 

2.     void main()

3.     {

4.         static int x = 3;

5.         x++;

6.         if (x <= 5)

7.         {

8.             printf("hi");

9.             main();

10.         }

11.     }

a) Run time error
b) hi
c) Infinite hi
d) hi hi

Answer: d

12. Which of the following is a correct format for declaration of function?

a) return-type function-name(argument type);
b) return-type function-name(argument type)
{}
c) return-type (argument type)function-name;
d) all of the mentioned

Answer: a

13. Which of the following function declaration is illegal?

a) int 1bhk(int);
b) int 1bhk(int a);
c) int 2bhk(int*, int []);
d) all of the mentioned

Answer: d

14. Which function definition will run correctly?

a) int sum(int a, int b)
    return (a + b);
b) int sum(int a, int b)
    {return (a + b);}
c) int sum(a, b)
    return (a + b);
d) none of the mentioned

Answer: b

15. Can we use a function as a parameter of another function? [ Eg: void wow(int func()) ].

a) Yes, and we can use the function value conveniently
b) Yes, but we call the function again to get the value, not as convenient as in using variable
c) No, C does not support it
d) This case is compiler dependent

Answer: c

16. The value obtained in the function is given back to main by using ________ keyword?

a) return
b) static
c) new
d) volatile

Answer: a