Deep copy and Shallow copy w.r.t Copy Constructor and Assignment Operator

Hi to Everyone.

Its been a long time, I have been searching for an clear cut idea of
....shallow copy and deep copy with regards to Copy constructor and assignment operator.

I search the web, but many places has been confused me...I know that the problem comes only when we do use of pointers...But, dont know exact situation and solution for it. when to use which one..ie in which situation to used which one....

Can anyone please help me understanding the concept better.

A good example problem with relating to all these topic would be appreciated.
May be could you please relate the example with the following situations

1. Default copy constructor
2. Default assignment operator
3. overloaded copy constructor
4. overloaded assignment operator

Thanks in advance

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I am a beginner