DXCorr Hardware Technologies HR Executive Generalist Interview Questions and Answers

Hashmap is a data structure that stores key-value pairs and allows constant time access to values.

• Hashmap uses a hash function to map keys to indices in an array.

• Collisions can occur when multiple keys map to the same index, which can be resolved using techniques like chaining or open addressing.

• Hashmap operations like insertion, deletion, and lookup have an average time complexity of O(1).

References and pointers are both used to refer to memory locations, but references cannot be null and cannot be reseated.

• Pointers can be null or uninitialized

• Pointers can be reseated to point to a different memory location

• References are automatically dereferenced

• References cannot be used with arrays

• Pointers can be used with arrays

References are necessary when passing large objects to functions or when returning objects from functions.

• When passing large objects to functions

• When returning objects from functions

• When working with complex data structures

• When implementing operator overloading

• When working with polymorphism

Const pointers should be declared in the same scope as the variable they point to.

• Declaring const pointers in the same scope as the variable they point to ensures that the pointer cannot be used to modify the variable.

• If the pointer is only used within a function, it should be declared within that function.

• If the pointer is used across multiple functions, it should be declared in a header file or at the top of the sour...read more

Copy constructor with pointers creates a new object by copying the values of the existing object's pointers.

• Copy constructor is used to create a new object from an existing object.

• Pointers in the new object point to the same memory locations as the original object.

• Deep copy should be used to avoid shallow copy issues.

new and malloc are used for dynamic memory allocation in C++ and C respectively.

• new is an operator in C++ while malloc is a function in C.

• new automatically calls the constructor while malloc does not.

• new returns a pointer to the object while malloc returns a void pointer.

• new throws an exception if allocation fails while malloc returns NULL.

• new can be overloaded while malloc cannot be.

• new and delete are used together wh