Differentiate between a deep copy and a shallow copy?
Answer Posted / ritesh pal
Deep copy involves using the contents of one object to create another instance of the same class. In a deep copy, the two objects may contain ht same information but the target object will have its own buffers and resources. the destruction of either object will not affect the remaining object. The overloaded assignment operator would create a deep copy of objects.
Shallow copy involves copying the contents of one object into another instance of the same class thus creating a mirror image. Owing to straight copying of references and pointers, the two objects will share the same externally contained contents of the other object to be unpredictable.
Explanation:
Using a copy constructor we simply copy the data values member by member. This method of copying is called shallow copy. If the object is a simple class, comprised of built in types and no pointers this would be acceptable. This function would use the values and the objects and its behavior would not be altered with a shallow copy, only the addresses of pointers that are members are copied and not the value the address is pointing to. The data values of the object would then be inadvertently altered by the function. When the function goes out of scope, the copy of the object with all its data is popped off the stack.
If the object has any pointers a deep copy needs to be executed. With the deep copy of an object, memory is allocated for the object in free store and the elements pointed to are copied. A deep copy is used for objects that are returned from a function.
| Is This Answer Correct ? | 0 Yes | 0 No |
Post New Answer View All Answers
What are arithmetic operators?
What is do..while loops structure?
What is private inheritance?
What is #include sstream?
What is the basic of c++?
What do you mean by ‘void’ return type?
What is the function to call to turn an ascii string into a long?
Distinguish between a # include and #define.
What is ios :: in in c++?
What are its advantages and disadvantages of multiple inheritances (virtual inheritance)?
What is the difference between the functions memmove() and memcpy()?
If you want to share several functions or variables in several files maitaining the consistency how would you share it?
Explain about Virtual Function in C++?
What is #include ctype h in c++?
What are the three forms of cin.get() and what are their differences?