C Programming Questions and Answers on Self-Referential Structures for Freshers

1. What is the output of this C code?

1.     #include 

2.     typedef struct p *q;

3.     int main()

4.     {

5.         struct p

6.         {

7.             int x;

8.             char y;

9.             q ptr;

10.         };

11.         struct p p = {1, 2, &p};

12.         printf("%d\n", p.ptr->x);

13.         return 0;

14.     }

a) Compile time error
b) 1
c) Depends on the compiler
d) None of the mentioned

Answer: a

2. What is the output of this C code?

1.     #include 

2.     int main()

3.     {

4.         typedef struct p *q;

5.         struct p

6.         {

7.             int x;

8.             char y;

9.             q ptr;

10.         };

11.         struct p p = {1, 2, &p};

12.         printf("%d\n", p.ptr->x);

13.         return 0;

14.     }

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

Answer: b

3. What is the output of this C code?

1.     #include 

2.     typedef struct p *q;

3.     struct p

4.     {

5.         int x;

6.         char y;

7.         q ptr;

8.     };

9.     int main()

10.     {

11.         struct p p = {1, 2, &p};

12.         printf("%d\n", p.ptr->ptr->x);

13.         return 0;

14.     }

a) Compile time error
b) Segmenation fault
c) Undefined behaviour
d) 1

Answer: d

4. The number of distinct nodes the following struct declaration can point to is.

1.     struct node

2.     {

3.         struct node *left;

4.         struct node *centre;

5.         struct node *right;

6.     };

a) 1
b) 2
c) 3
d) All of the mentioned

Answer: d

5. Which of the following is not possible?

a) A structure variable pointing to itself
b) A structure variable pointing to another structure variable of same type
c) 2 different type of structure variable pointing at each other
d) None of the mentioned

Answer: d

6. Which of the following techinique is faster for travelling in binary trees?

a) Iteration
b) Recursion
c) Both Iteration and Recursion
d) Depends from compiler to compiler

Answer: b

7. For the following declaration of structure, which of the following will stop the loop at the last node of a linked list?

1.     struct node

2.     {

3.         struct node *next;

4.     };

1. a) while (p != NULL)

2.     {

3.         p = p->next;

4.     }

5. b) while (p->next != NULL)

6.     {

7.         p = p->next;

8.     }

9. c) while (1)

10.     {

11.         p = p->next;

12.         if (p == NULL)

13.             break;

14.     }

15. d) All of the mentioned

Answer: b

8. What is the output of this C code?

1.     #include 

2.     struct student

3.     {

4.         char *c;

5.         struct student *point;

6.     };

7.     void main()

8.     {

9.         struct student s;

10.         struct student m;

11.         s.c = m.c = "hi";

12.         m.point = &s;

13.         (m.point)->c = "hey";

14.         printf("%s\t%s\t", s.c, m.c);

15.     }

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

Answer: a

9. What is the output of this C code?

1.     #include 

2.     struct student

3.     {

4.         char *c;

5.         struct student *point;

6.     };

7.     void main()

8.     {

9.         struct student s;

10.         struct student m;

11.         m.point = s;

12.         (m.point)->c = "hey";

13.         printf("%s", s.c);

14.     }

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

Answer: b

10. What is the output of this C code?

1.     #include 

2.     struct student

3.     {

4.         char *c;

5.         struct student point;

6.     };

7.     void main()

8.     {

9.         struct student s;

10.         s.c = "hello";

11.         printf("%s", s.c);

12.     }

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

Answer: d

11. What is the output of this C code?

1.     #include 

2.     struct student

3.     {

4.         char *c;

5.         struct student *point;

6.     };

7.     void main()

8.     {

9.         struct student s;

10.         printf("%d", sizeof(s));

11.     }

a) 5
b) 9
c) 8
d) 16

Answer: c

12. What is the output of this C code?

1.     #include 

2.     struct student

3.     {

4.         char *c;

5.         struct student *point;

6.     };

7.     void main()

8.     {

9.         struct student s;

10.         struct student *m = &s;

11.         printf("%d", sizeof(student));

12.     }

a) Compile time error
b) 8
c) 5
d) 16

Answer: a

13. What is the output of this C code?

1.     #include 

2.     struct p

3.     {

4.         int x;

5.         char y;

6.         struct p *ptr;

7.     };

8.     int main()

9.     {

10.         struct p p = {1, 2, &p};

11.         printf("%d\n", p.ptr->x);

12.         return 0;

13.     }

a) Compile time error
b) Undefined behaviour
c) 1
d) 2

Answer: c

14. What is the output of this C code?

1.     #include 

2.     typedef struct p *q;

3.     struct p

4.     {

5.         int x;

6.         char y;

7.         q ptr;

8.     };

9.     typedef struct p *q;

10.     int main()

11.     {

12.         struct p p = {1, 2, &p};

13.         printf("%d\n", p.ptr->x);

14.         return 0;

15.     }

a) Compile time error
b) 1
c) Undefined behaviour
d) Address of p

Answer: a