Top 10 C Language Interview Questions with Answers

Are you really preparing for a C interview and having too many questions to ponder? Then don't! Think of us as your support system. The following is a very concise list of the Top 10 C Language Interview Questions with Answers that will hopefully be your answer to that next big interview.

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1. What is C language?

Answer:

Think of C as a general-purpose procedural programming language designed by Dennis Ritchie in the 1970s; It meets our needs for system programming because of its fast speed, simplicity, and ability to access low-level memory.

2. What are the basic data types in C?

Answer:

They are basic data types, which include:

• int (Integer)

• float (Floating-point)

• char (Character)

• double (Double precision floating-point)

3. What is a pointer in C?

Answer:

In C, a pointer is a variable that keeps the memory address of another variable. It is used for creating dynamic memory management and working with arrays efficiently.

4. What is the difference between ++i and i++?

Answer:

++i means increment NOW, i. e., increment before using in any expression; i++ means use the current value of the variable in an expression and then increment it.

5. What is the use of sizeof operator?

Answer:

It returns the size of memory (in bytes) that a data type occupies. For instance, sizeof(int) may return 4.

6. What is the difference between call by value and call by reference?

Answer:

• Call by value: passes the copy of the variable, so changes made inside the function do not affect the original.

• Call by reference: passes the actual address so that changes modify the real variable.

7. What are storage classes in C?

Answer:

Storage classes tell us about the scope, lifetime, and visibility of variables:

• auto

• extern

• static

• register

8. What is recursion in C?

Answer:

Recursion is a condition wherein the function calls itself. It’s generally applied for calculating factorials or Fibonacci values.

9. What is a NULL pointer?

Answer:

A NULL pointer is a pointer that points to no location in memory. It is used for error handling and safe pointer initialization.

10. How would you differentiate between structure and union?

Structures allocate separate memory spaces to each member.

Unions allocate the same space in memory to all members, which saves space but allows it to hold only one value at a time.

Conclusion

These top 10 questions are about some of the basic concepts of C that are normally asked in interviews. So having command over these will surely be very helpful in boosting your confidence and making you a stronger candidate.

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