Basic C Interview Questions

These are few basic Interview questions in C .....

1)How do we check whether a linked list is circular?

2)What is the output of this program?

#include
##include
main()
{
typedef union
{
int a;
char b[10];
float c;
}
Struct;

Struct x,y = {100};
x.a = 50;
strcpy(x.b,"hello");
x.c = 21.50;

printf("Union x : %d %s %f \n",x.a,x.b,x.c );
printf("Union y : %d %s %f \n",y.a,y.b,y.c);
}

3)What is a Null object?

4)Name some pure object oriented languages.

5)What is a container class? What are the different types of container classes?

6)What will be the output of the following program:
#include
main()
{
printf("%x",-1<<4);
}

7)What are the major differences between C and C++?

8)What is an incomplete type?

9)What are printf and scanf, call by reference or call by value?

10)What is a const pointer?

11)When should a type cast be used and when should it not be used?

12)Which is the easiest sorting method?

13)Which is the quickest sorting method?

14)Which are the best sorting algorithms to sort a linked list?

15)What is a preprocessor and what will it do for a program?

16)How can a string be converted into a number?

17)How can a number be converted into a string?

18)What is a heap?

19)Why does n++ execute much faster than n+1?

20)What is modular Programming?

21)Which expression always returns true and which expression always returns false?

22)What is the difference between "malloc" and "calloc"?

23)Is C
a)A low level language
b)A middle level language
c)A high level language ?

24)Why doesn't C support function overloading?

25)What is the difference between global int & static int declaration?


Click here for the solutions

20 comments:

  1. Hello. Could you please clear the 19th Question. The question asks difference between n++ and n+1, but the solution gives the explanation for n++ and ++n .

    But i hope the question really meant d/b n++ and ++n , coz i was asked the same question in an interview, n i gave this same answer.! fingers crossed.

    Thank you again.

    ReplyDelete
    Replies
    1. +n is faster than n++ is faster than n=n+1
      Machine usually have increment x as well as add const to x

      In case of n++, you will have 2 memory access only (read n, inc n, write n )
      In case of n=n+1, you will have 3 memory access (read n, read const, add n and const, write n)

      Delete
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    ReplyDelete
  3. questios are very logical for basics
    answeers should b beside the questions

    ReplyDelete
  4. 2nd question:
    how y.b value is d?

    ReplyDelete
  5. give the answer for that questions

    ReplyDelete
  6. please give ans to the ques

    ReplyDelete
  7. C Interview Questions and Answers for campus placement preparation at gyantonic.com

    ReplyDelete
  8. amzing qestions...fully satisfied with answrs.....

    ReplyDelete
  9. plz give me answer of these questions

    ReplyDelete
  10. I enjoy this 25 questions on c interview questions, but I want some basic c interview questions along with answer like website
    programmerinterview

    ReplyDelete
  11. here i can improve my knowledge about c...this is very useful questions..thank you for the author...can u send me more questions and puzzles?

    ReplyDelete
  12. plz give me answer for those questions

    ReplyDelete
  13. BASIC C INTERVIEW QUESTIONS AND ANSWERS

    http://www.tecz.org/interview-questions/105-basic-c-interview-questines-and-answers.html

    ReplyDelete
  14. Hey, could you provide the answers to these question. Here is another site, with some interesting C interview questions along with their answers,

    http://www.codewithc.com/most-common-c-interview-questions-answers/

    ReplyDelete
  15. its simply nice

    Frequently Asked C Language Interview Questions and answers

    www.fresherventure.net/frequently-asked-c-language..

    ReplyDelete