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Assignment Operator - What is the diffrence between a "assignment operator" and a "copy constructor"?

C++ Interview Questions and Answers

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Assignment Operator - What is the diffrence between a "assignment operator" and a "copy constructor"?

Answer1.
In assignment operator, you are assigning a value to an existing object. But in copy constructor, you are creating a new object and then assigning a value to that object. For example: 

complex c1,c2;
c1=c2; //this is assignment
complex c3=c2; //copy constructor


Answer2.
A copy constructor is used to initialize a newly declared variable from an existing variable. This makes a deep copy like assignment, but it is somewhat simpler:

There is no need to test to see if it is being initialized from itself.
There is no need to clean up (eg, delete) an existing value (there is none).
A reference to itself is not returned.

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