Add to Favorites    Make Home Page 14285 Online  
 Language Categories  
 Our Services  

Home » C Home » Beginners / Lab Assignments Home » INTERVIEW QUESTIONS C

A D V E R T I S E M E N T

Search Projects & Source Codes:

Title INTERVIEW QUESTIONS C
Author Rajarathnam.l
Author Email rajara2004 [at] yahoo.co.in
Description This is faq asked in interview provided with answer for the
better understanding of job seekers.
Category C » Beginners / Lab Assignments
Hits 383052
Code Select and Copy the Code
Predict the output or error(s) for the following: 1. void main() { int const * p=5; printf("%d",++(*p)); } Answer: Compiler error: Cannot modify a constant value. Explanation: p is a pointer to a "constant integer". But we tried to change the value of the "constant integer". 2. main() { char s[ ]="man"; int i; for(i=0;s[ i ];i++) printf(" %c%c%c%c",s[ i ],*(s+i),*(i+s),i[s]); } Answer: mmmm aaaa nnnn Explanation: s[i], *(i+s), *(s+i), i[s] are all different ways of expressing the same idea. Generally array name is the base address for that array. Here s is the base address. i is the index number/displacement from the base address. So, indirecting it with * is same as s[i]. i[s] may be surprising. But in the case of C it is same as s[i]. 3. main() { float me = 1.1; double you = 1.1; if(me==you) printf("I love U"); else printf("I hate U"); } Answer: I hate U Explanation: For floating point numbers (float, double, long double) the values cannot be predicted exactly. Depending on the number of bytes, the precession with of the value represented varies. Float takes 4 bytes and long double takes 10 bytes. So float stores 0.9 with less precision than long double. Rule of Thumb: Never compare or at-least be cautious when using floating point numbers with relational operators (== , >, <, <=, >=,!= ) . 4. main() { static int var = 5; printf("%d ",var--); if(var) main(); } Answer: 5 4 3 2 1 Explanation: When static storage class is given, it is initialized once. The change in the value of a static variable is retained even between the function calls. Main is also treated like any other ordinary function, which can be called recursively. 5. main() { int c[ ]={2.8,3.4,4,6.7,5}; int j,*p=c,*q=c; for(j=0;j<5;j++) { printf(" %d ",*c); ++q; } for(j=0;j<5;j++){ printf(" %d ",*p); ++p; } } Answer: 2 2 2 2 2 2 3 4 6 5 Explanation: Initially pointer c is assigned to both p and q. In the first loop, since only q is incremented and not c , the value 2 will be printed 5 times. In second loop p itself is incremented. So the values 2 3 4 6 5 will be printed. 6. main() { extern int i; i=20; printf("%d",i); } Answer: Linker Error : Undefined symbol '_i' Explanation: extern storage class in the following declaration, extern int i; specifies to the compiler that the memory for i is allocated in some other program and that address will be given to the current program at the time of linking. But linker finds that no other variable of name i is available in any other program with memory space allocated for it. Hence a linker error has occurred . 7. main() { int i=-1,j=-1,k=0,l=2,m; m=i++&&j++&&k++||l++; printf("%d %d %d %d %d",i,j,k,l,m); } Answer: 0 0 1 3 1 Explanation : Logical operations always give a result of 1 or 0 . And also the logical AND (&&) operator has higher priority over the logical OR (||) operator. So the expression �i++ && j++ && k++� is executed first. The result of this expression is 0 (-1 && -1 && 0 = 0). Now the expression is 0 || 2 which evaluates to 1 (because OR operator always gives 1 except for �0 || 0� combination- for which it gives 0). So the value of m is 1. The values of other variables are also incremented by 1. 8. main() { char *p; printf("%d %d ",sizeof(*p),sizeof(p)); } Answer: 1 2 Explanation: The sizeof() operator gives the number of bytes taken by its operand. P is a character pointer, which needs one byte for storing its value (a character). Hence sizeof(*p) gives a value of 1. Since it needs two bytes to store the address of the character pointer sizeof(p) gives 2. 9. main() { int i=3; switch(i) { default:printf("zero"); case 1: printf("one"); break; case 2:printf("two"); break; case 3: printf("three"); break; } } Answer : three Explanation : The default case can be placed anywhere inside the loop. It is executed only when all other cases doesn't match. 10. main() { printf("%x",-1<<4); } Answer: fff0 Explanation : -1 is internally represented as all 1's. When left shifted four times the least significant 4 bits are filled with 0's.The %x format specifier specifies that the integer value be printed as a hexadecimal value. 11. main() { char string[]="Hello World"; display(string); } void display(char *string) { printf("%s",string); } Answer: Compiler Error : Type mismatch in redeclaration of function display Explanation : In third line, when the function display is encountered, the compiler doesn't know anything about the function display. It assumes the arguments and return types to be integers, (which is the default type). When it sees the actual function display, the arguments and type contradicts with what it has assumed previously. Hence a compile time error occurs. 12. main() { int c=- -2; printf("c=%d",c); } Answer: c=2; Explanation: Here unary minus (or negation) operator is used twice. Same maths rules applies, ie. minus * minus= plus. Note: However you cannot give like --2. Because -- operator can only be applied to variables as a decrement operator (eg., i--). 2 is a constant and not a variable. 13. #define int char main() { int i=65; printf("sizeof(i)=%d",sizeof(i)); } Answer: sizeof(i)=1 Explanation: Since the #define replaces the string int by the macro char 14. main() { int i=10; i=!i>14; printf("i=%d",i); } Answer: i=0 Explanation: In the expression !i>14 , NOT (!) operator has more precedence than � >� symbol. ! is a unary logical operator. !i (!10) is 0 (not of true is false). 0>14 is false (zero). 15. #include<stdio.h> main() { char s[]={'a','b','c',' ','c','

Related Source Codes

Script Name Author
The Game Opposite as seen on Nokia 2300 Mobile Manikanta
RECURSIVE BALANCED QUICK SORT ashish
Radix Sort ashish
Change your mouse pointer Ashim
The blinking star Shashank
Data Validation Crylittlebaby
To search a file by giving file type like mp3 or mpeg or doc Prashanth SR
Menus Demonstration B.Chidhambaram
Employee Database Project Using C. Reenku Raman Nayak
Creating a Lexical Analyzer in c fahad bader al-buhairi �դ ?�� ��??���
Calendar Program Omkar & Devendra
Stop double Process for start in C Cedrik Jurak
Stop double Process for start in C Cedrik Jurak
Time Scheduler Atiq Anwar
A timepass game between atmost two players Rahul Roy

A D V E R T I S E M E N T




Google Groups Subscribe to SourceCodesWorld - Techies Talk
Email:

Free eBook - Interview Questions: Get over 1,000 Interview Questions in an eBook for free when you join JobsAssist. Just click on the button below to join JobsAssist and you will immediately receive the Free eBook with thousands of Interview Questions in an ebook when you join.

New! Click here to Add your Code!


ASP Home | C Home | C++ Home | COBOL Home | Java Home | Pascal Home
Source Codes Home Page

 Advertisements  

Google Search

Google

Source Codes World.com is a part of Vyom Network.

Vyom Network : Web Hosting | Dedicated Server | Free SMS, GRE, GMAT, MBA | Online Exams | Freshers Jobs | Software Downloads | Interview Questions | Jobs, Discussions | Placement Papers | Free eBooks | Free eBooks | Free Business Info | Interview Questions | Free Tutorials | Arabic, French, German | IAS Preparation | Jokes, Songs, Fun | Free Classifieds | Free Recipes | Free Downloads | Bangalore Info | Tech Solutions | Project Outsourcing, Web Hosting | GATE Preparation | MBA Preparation | SAP Info | Software Testing | Google Logo Maker | Freshers Jobs

Sitemap | Privacy Policy | Terms and Conditions | Important Websites
Copyright ©2003-2024 SourceCodesWorld.com, All Rights Reserved.
Page URL: http://www.sourcecodesworld.com/source/show.asp?ScriptID=570


Download Yahoo Messenger | Placement Papers | Free SMS | C Interview Questions | C++ Interview Questions | Quick2Host Review