Output of program

[Akki 92]

I am new to c++.
Can someone tell me the flow of the program.

#include <iostream>

class A
{
public:
A(int n = 0)
: m_n(n)
{
++m_ctor1_calls;
}

A(const A& a)
: m_n(a.m_n)
{
++m_copy_ctor_calls;
}

public:
static int m_ctor1_calls;
static int m_copy_ctor_calls;

private:
int m_n;
};

int A::m_ctor1_calls = 0;
int A::m_copy_ctor_calls = 0;

void f(const A &a1, const A &a2 = A())
{
}

int main()
{
A a(2), b = 5;
const A c(a), &d = c, e = b;
std::cout << A::m_ctor1_calls << A::m_copy_ctor_calls;
b = d;
A *p = new A(c), *q = &a;
std::cout << A::m_copy_ctor_calls;
delete p;
f(3);
std::cout << A::m_ctor1_calls << A::m_copy_ctor_calls << std::endl;

return 0;

}

[samarjan]

your program counts how many times a copy constructor ana a constructor are called