Explain what is a class in C? A class in C can be defined as a collection of function and related. C is created by Bjarne Stroustrup of AT&T Bell Labs as an extension of C, C is an.

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1) What will be the output of printf(“%d”)?

The first argument which contains strings to be printed or format specifiers is mandatory. Other than that, the arguments are optional.So, in case of only %d used without any variable in printf, the compiler may generate warning but will not cause any error. In this case, the correct offset based on %d is calculated by compiler but as the actual data variable is not present in that calculated location of memory, the printf will fetch integer size value and print whatever is there (which is garbage value to us).

The printf function upon successful return, returns the number of characters printed in output device. So, printf(“A”) will return 1. The scanf function returns the number of input items successfully matched and assigned, which can be fewer than the format specifiers provided. It can also return zero in case of early matching failure.

3) How to free a block of memory previously allocated without using free?

If the pointer holding that memory address is passed to realloc with size argument as zero (like realloc(ptr, 0)) the the memory will be released.

4) How can you print a string containing '%' in printf?

There are no escape sequence provided for '%' in C. To print '%' one should use '%%', like -

C Language Interview Questions And Answers For Freshers Pdf Sample

5) What is use of %n in printf()?

Ans: According to man page “the number of characters written so far is stored into the integer. indicated by the int * (or variant) pointer argument.“. Meaning if we use it in printf, it will get the number of characters already written until %n is encountered and this number will stored in the variable provided. The variable must be an integer pointer.

Above program will print 'Hello world 5 “ as Hello is 5 letter.

6) Swap two variables without using any control statement ?

We can swap variable using 2 methods. First method is as given below

Second method to swap variables is given below

7) Consider the two structures Struct A and Struct B given below. What will be size of these structures?

struct A
{
unsigned char c1 : 3;
unsigned char c2 : 4;
unsigned char c3 : 1;
}a;

struct A
{
unsigned char c1 : 3;
unsigned char : 0;
unsigned char c2 : 4;
unsigned char c3 : 1;
}a;

The size of the structures will be 1 and 2. In case of first structure, the members will be assigned a byte as follows -

But in case of second structure -

The :0 field (0 width bit field) forces the next bit width member assignment to start from the next nibble. By doing so, the c3 variable will be assigned a bit in the next byte, resulting the size of the structure to 2.

8) How to call a function before main()?

To call a function pragma startup directive should be used. Pragma startup can be used like this -

The output of the above program will be -

But this pragma directive is compiler dependent. Gcc does not support this. So, it will ignore the startup directive and will produce no error. But the output in that case will be -

9) What is rvalue and lvalue?

You can think lvalue as a left side operant in an assignment and rvalue is the right. Also, you can remember lavlue as location. So, the lvalue means a location where you can store any value. Say, for statement i = 20, the value 20 is to be stored in the location or address of the variable i. 20 here is rvalue. Then the 20 = I, statement is not valid. It will result in compilation error “lvalue required” as 20 does not represent any location.

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10)How to pack a structure?

We can pack any structure using __attribute__((__packed__)) in gcc. Example -

We can also use, pragma pack like this -

In both cases the size of the structure will be 5. But remember, the pragma pack and the other method mentioned, both are compiler dependent.

11) How to convert a string to integer value?

We can convert a string to integer in two ways. Method 1:

Method 2:

12) Print the output of the following switch case program?

Output of this program will be 3. The position of the default is before case 1. So, even if there is no break after case 3, the execution will just exit switch case and it will not go to default case.

13) How to prevent same header file getting included multiple times?

We can use ifndef and define preprocessors. Say the header file is hdrfile.h, then we can write the header file like -

The ifndef will check whether macro HDRFILE_H_ is defined or not. If it is not defined, it will define the macro. From next time onward the statements inside ifndef will not be included.

14) Which is better #define or enum?

• Enum values can be automatically generated by compiler if we let it. But all the define values are to be mentioned specifically.
• Macro is preprocessor, so unlike enum which is a compile time entity, source code has no idea about these macros. So, the enum is better if we use a debugger to debug the code.
• If we use enum values in a switch and the default case is missing, some compiler will give a warning.
• Enum always makes identifiers of type int. But the macro let us choose between different integral types.
• Macro does not specifically maintain scope restriction unlike enum. For example -

Above program will print -

15) Print the output of this pointer program?

The program will crash. The pointer p points to string “Pointers”. But the string in constant and C will not allow to change its values. Forcibly doing so, like we did it, will cause crash of the program.

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TCS Interview Questions: TCS full form is Tata Consultancy Services and it is a global leader in IT services. TCS offers best career opportunities for fresher’s as well as Experienced. TCS Recruits number of candidates every year through Campus recruitment and direct walk-in.

TCS Selection Process:

Selecting of Candidates for TCS will be done in 3 phases.

• Written Test.
• Technical Interview.
• HR interview.

All are elimination rounds. We provide a wide collection for successful clearing of all the rounds. The aptitude which is the major part in the written test is provided. Follow the link Sample Quantitative Aptitude Questions.

Here we also provide wide collection of Technical Interview Questions and answers covering all the languages which will help a lot in clearing the Technical phase.

HR round TCS Interview Questions and Answers for Freshers

• Tell us something about yourself/ Introduce yourself

This is the most frequently asked question almost every company. Answer to this question should be very brief covering your educational background, family details, achievements and goals etc.

• Why should we hire you for TCS?

Your answer should be in that way that it convinces him to select you. Mention all the skills you have which will meet their requirement. Also mention your achievements which add benefit to their company.

• Who is the founder of TCS?

Jamsetji Nusserwanji Tata established TATA Group in 1869. However it was under Mr. Jahangir Ratanji Dadabhoy Tata (JRD Tata), that this group was expanded and hence TCS was established in 1968. Present Mr. Rattan Tata is the Chairman of the group.

• Who is the present CEO?

Mr. Natarajan Chandrasekaran is the present Chief Executive Officer (CEO).

If you can’t answer these questions it creates impression that you have not done any home work regarding this.

• Who are competitors for TCS?

A little study will help you answer this question which makes a positive sense to the interviewer that you are concerned with this job.

The major competitors for TCs are Infosys, Wipro, HCL, oracle, Tech Mahindra and Mphasis.

• Are you willing to accept a bond of 2 years and to relocate?

The answer to this question is up to you based on your personal and family conditions. Be honest.

• Why do you want to join TCS but no other companies?

Try to mention some of the positive factors such as Good work environment and career growth.

Ex: I heard from my friends that TCS has a very good work environment and career growth. More over TCS is one of the top IT companies. Never mention reasons like salary which creates negative impression.

• If you are rejected today what will you do?

This question doesn’t mean that you are rejected. This is test your confidence and also to know what are your other plans and to know if you have applied for any other company.

• Are you willing to work overtime and nights/weekends?

The answer to this question depends upon on one’s individual opinion and situations.

• Do you have anything to ask me?

You may ask questions of this kind

• what are the company policies regarding training?
• can you explain a typical day in this role?
• job description assigned to me be based on my interest area?
• what are the personal growth opportunities such as leadership training
• what is the training budget?

Few more questions would be like

• Who inspired you to become an engineer?
• Strengths and weaknesses
• Are you a team player
• Extra-curricular skills
• What is more important money or job?
• Dream job?
• Certification of skills
• Family background
• About your native place

You can see more Interview questions and answers pdf and details of TCS Careers in this links.

Finally the perfect preparation with all the above provided materials along with TCS interview questions and proper presentation with confidence and a bit of luck will transform you from student TCS employee. All the best.

How to Download TCS Interview Questions as PDF File:

You can use the links in this post to download more interview questions. If you want to save these questions as pdf document the use the save as pdf file option in the print settings.

This is a nice initiative to educate the job aspirants and get them prepare for such big companies .The questions are the common ones but at personal level it is much difficult for Freshers to answer them . Thank you