Copy constructor vs assignment operator in C++


Difficulty Level: Rookie

Consider the following C++ program.


using namespace std;

class Test
   Test() {}
   Test(const Test &t)
      cout<<"Copy constructor called "<<endl;
   Test& operator = (const Test &t)
      cout<<"Assignment operator called "<<endl;

int main()
  Test t1, t2;
  t2 = t1;
  Test t3 = t1;
  return 0;

Assignment operator called
Copy constructor called

Copy constructor is called when a new object is created from an existing object, as a copy of the existing object (see this G-Fact). And assignment operator is called when an already initialized object is assigned a new value from another existing object.

  t2 = t1;  // calls assignment operator, same as "t2.operator=(t1);"
  Test t3 = t1;  // calls copy constructor, same as "Test t3(t1);"


Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

GATE CS Corner    Company Wise Coding Practice

Please write to us at to report any issue with the above content.

Recommended Posts:

2.4 Average Difficulty : 2.4/5.0
Based on 29 vote(s)