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100 C Programming Interview Questions With Answers - Technical Interview.

C Programs Frequently Asked In Interviews.

This section covers C Programming Language questions often asked in campus interviews and freshers walk-in. This page will help job seekers who are about to attend TECHNICAL interview round.

Here you will find simple C programming questions with answers basically asked in technical interviews.

Click on any question to find out it's answers:

1) What is the difference between declaring a variable and defining a variable?
2) Define static variable?
3) What is a register variable?
4) Where is an auto variable stored?
5) What is meant by scope and storage allocation of a variable or function?

6) What is scope & storage allocation of extern and global variables?
7) What is scope & storage allocation of register?
8) What is scope & storage allocation of static and local variables?
9) What is the difference between 'break' and 'continue' statements?
10) What is the difference between uses of 'FOR' and 'WHILE' loops?

11) Which bitwise operator is used for checking whether a particular bit is ON or OFF?
12) Which bitwise operator is used for turning OFF a particular bit in a number?
13) What is equivalent of multiplying an unsigned int by 2: left shift of number by 1 or right shift of number by 1?
14) What is Enumeration?
15) What is a structure?

16) What are the differences between a structure and a union?
17) What is meant by union?
18) What are the advantages of unions?
19) How can typedef be used to define a type of structure?
20) What is enumeration constant?

21) What is the purpose of main() function?
22) What are the differences between formal arguments and actual arguments of a function?
23) What is call by value in functions?
24) What is call by reference in functions?
25) What are the differences between getchar() and scanf() functions for reading strings?

26) Out of the functions fgets() and gets(), which one is safer to use and why?
27) What is the difference between the functions strdup() and strcpy()?
28) What is recursive function?
29) What is the difference between defining and declaring a variable?
30) What is a constant variable?

31) What is a far pointer in C?
32) What are the uses of the void data type?
33) What is a pointer in C?
34) What are the advantages of using pointers?
35) What are the differences between malloc() and calloc()?

36) What is the purpose of the free() function?
37) How to use realloc() to dynamically increase size of an already allocated array?
38) What is the purpose of the sizeof() operator?
39) What is a wild pointer in C?
40) What is the purpose of the do-while loop in C?

41) What is the size of the void pointer in C?
42) What is a nested loop in C?
43) What are the operations performed on C++ lists?
44) How is searching in an array list carried out?
45) Where can an element are inserted in an array list?

46) How is deletion in an array list carried out?
47) What are the advantages of array lists?
48) What are the disadvantages of an array list?
49) What is a linked list in C?
50) What is a node?

51) What are the uses of pointers in C Programming?
52) What is the difference between call by value and call by reference (or Pass by value or pass by reference)?
53) What is a huge pointer?
54) What is near pointer?
55) In C, why is the void pointer useful? When would you use it?

56) What is a NULL Pointer? Whether it is same as an uninitialized pointer?
57) Are pointers integer?
58) What does the error ‘Null Pointer Assignment’ means and what causes this error?
59) What is generic pointer in C?
60) How pointer variables are initialized?

61) What is static memory allocation?
62) What is dynamic memory allocation?
63) What is the purpose of realloc?
64) What is pointer to a pointer?
65) What is an array of pointers?

66) Difference between array and pointer?
67) Difference between a array name and a pointer variable?
68) Difference between an array of pointers and a pointer to an array?
69) What are the pointer declarations used in C?
70) Differentiate between a constant pointer and pointer to a constant?

71) What is the invalid pointer arithmetic?
72) What are the advantages of using array of pointers to string instead of an array of strings?
73) Are the expressions *ptr ++ and ++ *ptr same?



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