Frequently Asked Questions - Object oriented Concepts
· How do you write a program which produces its own source code as its output?
· How can I find the day of the week given the date?
· Why doesn't C have nested functions?
· What is the most efficient way to count the number of bits which are set in a value?
· How can I convert integers to binary or hexadecimal?
· How can I call a function, given its name as a string?
· How do I access command-line arguments?
· How can I return multiple values from a function?
· How can I invoke another program from within a C program?
· How can I access memory located at a certain address?
· How can I allocate arrays or structures bigger than 64K?
· How can I find out how much memory is available?
· How can I read a directory in a C program?
· How can I increase the allowable number of simultaneously open files?
· What's wrong with the call "fopen("c:\newdir\file.dat", "r")"?
· What is the output of printf("%d")
· What will happen if I say delete this
· Difference between "C structure" and "C++ structure".
· Diffrence between a "assignment operator" and a "copy constructor"
· Explain the need for "Virtual Destructor".
· Can we have "Virtual Constructors"?
· What are the different types of polymorphism?
· What are Virtual Functions? How to implement virtual functions in "C"
· What are the different types of Storage classes?
· What is Namespace?
· What are the types of STL containers?.
· Difference between "vector" and "array"?
· How to write a program such that it will delete itself after exectution?
· Can we generate a C++ source code from the binary file?
· What are inline functions?
· Talk sometiming about profiling?
· How many lines of code you have written for a single program?
· What is "strstream" ?
· How to write Multithreaded applications using C++?
· Explain "passing by value", "passing by pointer" and "passing by reference"
· Write any small program that will compile in "C" but not in "C++"
· Have you heard of "mutable" keyword?
· What is a "RTTI"?
· Is there something that I can do in C and not in C++?
· Why preincrement operator is faster than postincrement?
· What is the difference between "calloc" and "malloc"?
· What will happen if I allocate memory using "new" and free it using "free" or allocate sin "calloc" and free it using "delete"?
· What is Memory Alignment?
· Explain working of printf.
· Difference between "printf" and "sprintf".
· What is "map" in STL?
· When shall I use Multiple Inheritance?
· What are the techniques you use for debugging?
· How to reduce a final size of executable?
· Give 2 examples of a code optimization.
· What is inheritance?
· Difference between Composition and Aggregation.
· Difference: Sequence Diagrams, Collaboration Diagrams.
· Difference: 'uses', 'extends', 'includes'
· What shall I go for Package Diagram?
· What is Polymorphism?
· Is class an Object? Is object a class?
· Comment: C++ "includes" behavior and java "imports"
· What do you mean by "Realization"?
· What is a Presistent, Transient Object?
· What is the use of Operator Overloading?
· Does UML guarantee project success?
· Difference: Activity Diagram and Sequence Diagram.
· What is association?
· How to resolve many to many relationship?
· How do you represent static members and abstract classes in Class Diagram?
· What does static variable mean?
· What is a pointer?
· What is a structure?
· What are the differences between structures and arrays?
· In header files whether functions are declared or defined?
· What are macros? what are its advantages and disadvantages?
· Difference between pass by reference and pass by value?
· What is static identifier?
· Where are the auto variables stored?
· Where does global, static, local, register variables, free memory and C Program instructions get stored?
· Difference between arrays and linked list?
· What are enumerations?
· Describe about storage allocation and scope of global, extern, static, local and register variables?
· What are register variables? What are the advantage of using register variables?
· What is the use of typedef?
· Can we specify variable field width in a scanf() format string? If possible how?
· Out of fgets() and gets() which function is safe to use and why?
· Difference between strdup and strcpy?
· What is recursion?
· Differentiate between a for loop and a while loop? What are it uses?
· What are the different storage classes in C?
· Write down the equivalent pointer expression for referring the same element a[i][j][k][l]?
· What is difference between Structure and Unions?
· What the advantages of using Unions?
· What are the advantages of using pointers in a program?
· What is the difference between Strings and Arrays?
· In a header file whether functions are declared or defined?
· What is a far pointer? where we use it?
· How will you declare an array of three function pointers where each function receives two ints and returns a float?
· what is a NULL Pointer? Whether it is same as an uninitialized pointer?
· What is a NULL Macro? What is the difference between a NULL Pointer and a NULL Macro?
· What does the error 'Null Pointer Assignment' mean and what causes this error?
· What is near, far and huge pointers? How many bytes are occupied by them?
· How would you obtain segment and offset addresses from a far address of a memory location?
· Are the expressions arr and &arr same for an array of integers?
· Does mentioning the array name gives the base address in all the contexts?
· Explain one method to process an entire string as one unit?
· What is the similarity between a Structure, Union and enumeration?
· Can a Structure contain a Pointer to itself?
· How can we check whether the contents of two structure variables are same or not?
· How are Structure passing and returning implemented by the complier?
· How can we read/write Structures from/to data files?
· What is the difference between an enumeration and a set of pre-processor # defines?
· what do the 'c' and 'v' in argc and argv stand for?
· Are the variables argc and argv are local to main?
· What is the maximum combined length of command line arguments including the space between adjacent arguments?
· If we want that any wildcard characters in the command line arguments should be appropriately expanded, are we required to make any special provision? If yes, which?
· Does there exist any way to make the command line arguments available to other functions without passing them as arguments to the function?
· What are bit fields? What is the use of bit fields in a Structure declaration?
· To which numbering system can the binary number 1101100100111100 be easily converted to?
· Which bit wise operator is suitable for checking whether a particular bit is on or off?
· Which bit wise operator is suitable for turning off a particular bit in a number?
· Which bit wise operator is suitable for checking whether a particular bit is on or off?
· which one is equivalent to multiplying by 2:Left shifting a number by 1 or Left shifting an unsigned int or char by 1?
· Write a program to compare two strings without using the strcmp() function.
· Write a program to concatenate two strings.
· Write a program to interchange 2 variables without using the third one.
· Write programs for String Reversal & Palindrome check
· Write a program to find the Factorial of a number
· Write a program to generate the Fibinocci Series
· Write a program which employs Recursion
· Write a program which uses Command Line Arguments
· Write a program which uses functions like strcmp(), strcpy()? etc
· What are the advantages of using typedef in a program?
· How would you dynamically allocate a one-dimensional and two-dimensional array of integers?
· How can you increase the size of a dynamically allocated array?
· How can you increase the size of a statically allocated array?
· When reallocating memory if any other pointers point into the same piece of memory do you have to readjust these other pointers or do they get readjusted automatically?
· Which function should be used to free the memory allocated by calloc()?
· How much maximum can you allocate in a single call to malloc()?
· Can you dynamically allocate arrays in expanded memory?
· What is object file? How can you access object file?
· Which header file should you include if you are to develop a function which can accept variable number of arguments?
· Can you write a function similar to printf()?
· How can a called function determine the number of arguments that have been passed to it?
· Can there be at least some solution to determine the number of arguments passed to a variable argument list function?
· How do you declare the following:
· An array of three pointers to chars
· An array of three char pointers
· A pointer to array of three chars
· A pointer to function which receives an int pointer and returns a float pointer
· A pointer to a function which receives nothing and returns nothing
· What do the functions atoi(), itoa() and gcvt() do?
· Does there exist any other function which can be used to convert an integer or a float to a string?
· How would you use qsort() function to sort an array of structures?
· How would you use qsort() function to sort the name stored in an array of pointers to string?
· How would you use bsearch() function to search a name stored in array of pointers to string?
· How would you use the functions sin(), pow(), sqrt()?
· How would you use the functions memcpy(), memset(), memmove()?
· How would you use the functions fseek(), freed(), fwrite() and ftell()?
· How would you obtain the current time and difference between two times?
· How would you use the functions randomize() and random()?
· How would you implement a substr() function that extracts a sub string from a given string?
· What is the difference between the functions rand(), random(), srand() and randomize()?
· What is the difference between the functions memmove() and memcpy()?
· How do you print a string on the printer?
· Can you use the function fprintf() to display the output on the screen?
· What is an object?
· What is the difference between an object and a class?
· What is the difference between class and structure?
· What is public, protected, private?
· What are virtual functions?
· What is friend function?
· What is a scope resolution operator?
· What do you mean by inheritance?
· What is abstraction?
· What is polymorphism? Explain with an example.
· What is encapsulation?
· What do you mean by binding of data and functions?
· What is function overloading and operator overloading?
· What is virtual class and friend class?
· What do you mean by inline function?
· What do you mean by public, private, protected and friendly?
· When is an object created and what is its lifetime?
· What do you mean by multiple inheritance and multilevel inheritance? Differentiate between them.
· Difference between realloc() and free?
· What is a template?
· What are the main differences between procedure oriented languages and object oriented languages?
· What are generic functions and generic classes?
· Why do we use virtual functions?
· What do you mean by pure virtual functions?
· What are virtual classes?
· Does c++ support multilevel and multiple inheritance?
· What are the advantages of inheritance?
· When is a memory allocated to a class?
· What is the difference between declaration and definition?
· What is virtual constructors/destructors?
· In c++ there is only virtual destructors, no constructors. Why?
· What is late bound function call and early bound function call? Differentiate.
· How is exception handling carried out in c++?
· When will a constructor executed?
· What is Dynamic Polymorphism?
· Write a macro for swapping integers.
· How can I find the day of the week given the date?
· Why doesn't C have nested functions?
· What is the most efficient way to count the number of bits which are set in a value?
· How can I convert integers to binary or hexadecimal?
· How can I call a function, given its name as a string?
· How do I access command-line arguments?
· How can I return multiple values from a function?
· How can I invoke another program from within a C program?
· How can I access memory located at a certain address?
· How can I allocate arrays or structures bigger than 64K?
· How can I find out how much memory is available?
· How can I read a directory in a C program?
· How can I increase the allowable number of simultaneously open files?
· What's wrong with the call "fopen("c:\newdir\file.dat", "r")"?
· What is the output of printf("%d")
· What will happen if I say delete this
· Difference between "C structure" and "C++ structure".
· Diffrence between a "assignment operator" and a "copy constructor"
· Explain the need for "Virtual Destructor".
· Can we have "Virtual Constructors"?
· What are the different types of polymorphism?
· What are Virtual Functions? How to implement virtual functions in "C"
· What are the different types of Storage classes?
· What is Namespace?
· What are the types of STL containers?.
· Difference between "vector" and "array"?
· How to write a program such that it will delete itself after exectution?
· Can we generate a C++ source code from the binary file?
· What are inline functions?
· Talk sometiming about profiling?
· How many lines of code you have written for a single program?
· What is "strstream" ?
· How to write Multithreaded applications using C++?
· Explain "passing by value", "passing by pointer" and "passing by reference"
· Write any small program that will compile in "C" but not in "C++"
· Have you heard of "mutable" keyword?
· What is a "RTTI"?
· Is there something that I can do in C and not in C++?
· Why preincrement operator is faster than postincrement?
· What is the difference between "calloc" and "malloc"?
· What will happen if I allocate memory using "new" and free it using "free" or allocate sin "calloc" and free it using "delete"?
· What is Memory Alignment?
· Explain working of printf.
· Difference between "printf" and "sprintf".
· What is "map" in STL?
· When shall I use Multiple Inheritance?
· What are the techniques you use for debugging?
· How to reduce a final size of executable?
· Give 2 examples of a code optimization.
· What is inheritance?
· Difference between Composition and Aggregation.
· Difference: Sequence Diagrams, Collaboration Diagrams.
· Difference: 'uses', 'extends', 'includes'
· What shall I go for Package Diagram?
· What is Polymorphism?
· Is class an Object? Is object a class?
· Comment: C++ "includes" behavior and java "imports"
· What do you mean by "Realization"?
· What is a Presistent, Transient Object?
· What is the use of Operator Overloading?
· Does UML guarantee project success?
· Difference: Activity Diagram and Sequence Diagram.
· What is association?
· How to resolve many to many relationship?
· How do you represent static members and abstract classes in Class Diagram?
· What does static variable mean?
· What is a pointer?
· What is a structure?
· What are the differences between structures and arrays?
· In header files whether functions are declared or defined?
· What are macros? what are its advantages and disadvantages?
· Difference between pass by reference and pass by value?
· What is static identifier?
· Where are the auto variables stored?
· Where does global, static, local, register variables, free memory and C Program instructions get stored?
· Difference between arrays and linked list?
· What are enumerations?
· Describe about storage allocation and scope of global, extern, static, local and register variables?
· What are register variables? What are the advantage of using register variables?
· What is the use of typedef?
· Can we specify variable field width in a scanf() format string? If possible how?
· Out of fgets() and gets() which function is safe to use and why?
· Difference between strdup and strcpy?
· What is recursion?
· Differentiate between a for loop and a while loop? What are it uses?
· What are the different storage classes in C?
· Write down the equivalent pointer expression for referring the same element a[i][j][k][l]?
· What is difference between Structure and Unions?
· What the advantages of using Unions?
· What are the advantages of using pointers in a program?
· What is the difference between Strings and Arrays?
· In a header file whether functions are declared or defined?
· What is a far pointer? where we use it?
· How will you declare an array of three function pointers where each function receives two ints and returns a float?
· what is a NULL Pointer? Whether it is same as an uninitialized pointer?
· What is a NULL Macro? What is the difference between a NULL Pointer and a NULL Macro?
· What does the error 'Null Pointer Assignment' mean and what causes this error?
· What is near, far and huge pointers? How many bytes are occupied by them?
· How would you obtain segment and offset addresses from a far address of a memory location?
· Are the expressions arr and &arr same for an array of integers?
· Does mentioning the array name gives the base address in all the contexts?
· Explain one method to process an entire string as one unit?
· What is the similarity between a Structure, Union and enumeration?
· Can a Structure contain a Pointer to itself?
· How can we check whether the contents of two structure variables are same or not?
· How are Structure passing and returning implemented by the complier?
· How can we read/write Structures from/to data files?
· What is the difference between an enumeration and a set of pre-processor # defines?
· what do the 'c' and 'v' in argc and argv stand for?
· Are the variables argc and argv are local to main?
· What is the maximum combined length of command line arguments including the space between adjacent arguments?
· If we want that any wildcard characters in the command line arguments should be appropriately expanded, are we required to make any special provision? If yes, which?
· Does there exist any way to make the command line arguments available to other functions without passing them as arguments to the function?
· What are bit fields? What is the use of bit fields in a Structure declaration?
· To which numbering system can the binary number 1101100100111100 be easily converted to?
· Which bit wise operator is suitable for checking whether a particular bit is on or off?
· Which bit wise operator is suitable for turning off a particular bit in a number?
· Which bit wise operator is suitable for checking whether a particular bit is on or off?
· which one is equivalent to multiplying by 2:Left shifting a number by 1 or Left shifting an unsigned int or char by 1?
· Write a program to compare two strings without using the strcmp() function.
· Write a program to concatenate two strings.
· Write a program to interchange 2 variables without using the third one.
· Write programs for String Reversal & Palindrome check
· Write a program to find the Factorial of a number
· Write a program to generate the Fibinocci Series
· Write a program which employs Recursion
· Write a program which uses Command Line Arguments
· Write a program which uses functions like strcmp(), strcpy()? etc
· What are the advantages of using typedef in a program?
· How would you dynamically allocate a one-dimensional and two-dimensional array of integers?
· How can you increase the size of a dynamically allocated array?
· How can you increase the size of a statically allocated array?
· When reallocating memory if any other pointers point into the same piece of memory do you have to readjust these other pointers or do they get readjusted automatically?
· Which function should be used to free the memory allocated by calloc()?
· How much maximum can you allocate in a single call to malloc()?
· Can you dynamically allocate arrays in expanded memory?
· What is object file? How can you access object file?
· Which header file should you include if you are to develop a function which can accept variable number of arguments?
· Can you write a function similar to printf()?
· How can a called function determine the number of arguments that have been passed to it?
· Can there be at least some solution to determine the number of arguments passed to a variable argument list function?
· How do you declare the following:
· An array of three pointers to chars
· An array of three char pointers
· A pointer to array of three chars
· A pointer to function which receives an int pointer and returns a float pointer
· A pointer to a function which receives nothing and returns nothing
· What do the functions atoi(), itoa() and gcvt() do?
· Does there exist any other function which can be used to convert an integer or a float to a string?
· How would you use qsort() function to sort an array of structures?
· How would you use qsort() function to sort the name stored in an array of pointers to string?
· How would you use bsearch() function to search a name stored in array of pointers to string?
· How would you use the functions sin(), pow(), sqrt()?
· How would you use the functions memcpy(), memset(), memmove()?
· How would you use the functions fseek(), freed(), fwrite() and ftell()?
· How would you obtain the current time and difference between two times?
· How would you use the functions randomize() and random()?
· How would you implement a substr() function that extracts a sub string from a given string?
· What is the difference between the functions rand(), random(), srand() and randomize()?
· What is the difference between the functions memmove() and memcpy()?
· How do you print a string on the printer?
· Can you use the function fprintf() to display the output on the screen?
· What is an object?
· What is the difference between an object and a class?
· What is the difference between class and structure?
· What is public, protected, private?
· What are virtual functions?
· What is friend function?
· What is a scope resolution operator?
· What do you mean by inheritance?
· What is abstraction?
· What is polymorphism? Explain with an example.
· What is encapsulation?
· What do you mean by binding of data and functions?
· What is function overloading and operator overloading?
· What is virtual class and friend class?
· What do you mean by inline function?
· What do you mean by public, private, protected and friendly?
· When is an object created and what is its lifetime?
· What do you mean by multiple inheritance and multilevel inheritance? Differentiate between them.
· Difference between realloc() and free?
· What is a template?
· What are the main differences between procedure oriented languages and object oriented languages?
· What are generic functions and generic classes?
· Why do we use virtual functions?
· What do you mean by pure virtual functions?
· What are virtual classes?
· Does c++ support multilevel and multiple inheritance?
· What are the advantages of inheritance?
· When is a memory allocated to a class?
· What is the difference between declaration and definition?
· What is virtual constructors/destructors?
· In c++ there is only virtual destructors, no constructors. Why?
· What is late bound function call and early bound function call? Differentiate.
· How is exception handling carried out in c++?
· When will a constructor executed?
· What is Dynamic Polymorphism?
· Write a macro for swapping integers.