10+ Crescon Projects & Services Interview Questions and Answers

Singleton class ensures only one instance of a class is created and provides a global point of access to it.

• Ensures only one instance of a class is created

• Provides a global point of access to the instance

• Useful for managing global resources or settings

A function pointer is a variable that stores the address of a function. Its signature includes the return type and parameter types of the function.

• Function pointers allow for dynamic function calls based on the stored address

• Syntax: return_type (*pointer_name)(parameter_types)

• Example: void (*funcPtr)(int) = &someFunction;

STL libraries provide efficient and easy-to-use container classes like Vector for storing and manipulating data.

• STL Vector is a dynamic array that can resize itself automatically.

• It provides random access to elements, similar to arrays.

• Vector supports various operations like push_back, pop_back, insert, erase, etc.

• Example: std::vector<int> numbers = {1, 2, 3, 4, 5};

Use a loop to copy characters from one string to another

• Create two character arrays to store the strings

• Use a loop to iterate through each character of the source string and copy it to the destination string

• Add a null terminator at the end of the destination string to mark the end of the copied string

To delete a node from a linked list, update the pointers of the previous node to skip the node to be deleted.

• Traverse the linked list to find the node to be deleted

• Update the pointers of the previous node to skip the node to be deleted

• Free the memory allocated to the node to be deleted

Overload + operator to add two complex numbers in C++.

• Define a class for complex numbers with real and imaginary parts.

• Overload the + operator as a member function of the class.

• Return a new complex number with the sum of real and imaginary parts.

Compile time polymorphism is achieved through function overloading and templates in C++.

• Compile time polymorphism allows for different functions to be called based on the arguments provided at compile time.

• Function overloading is a form of compile time polymorphism where multiple functions have the same name but different parameters.

• Templates in C++ allow for generic programming and compile time polymorphism by creating functions or classes that can work with any data type.

• Co...read more

Mutex is used in multithreading to prevent multiple threads from accessing shared resources simultaneously.

• Mutex stands for mutual exclusion and is used to synchronize access to shared resources in multithreaded programs.

• It allows only one thread to access the shared resource at a time, preventing data corruption or race conditions.

• Mutexes are typically used in critical sections of code where data integrity is important.

• Example: Protecting a shared variable in a multithreaded...read more

Bit shift 1 by 4 positions from LSB results in 16

• Use the left shift operator (<<) to shift the bits by 4 positions

• 1 << 4 = 16

Runtime polymorphism allows objects of different classes to be treated as objects of a common superclass.

• Use virtual functions in base class and override them in derived classes

• Use pointers or references of base class to call derived class methods

• Example: Animal class with virtual function 'makeSound', Dog and Cat classes overriding 'makeSound'

Polymorphism is the ability of a function to behave differently based on the object it is called with.

• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• There are two types of polymorphism: compile-time (function overloading) and runtime (virtual functions).

• Example: A base class Animal with a virtual function 'makeSound'. Subclasses Dog and Cat override 'makeSound' to bark and meow respectively.