Why is copy constructor called in this case?
<p>I have these two simple classes: CreditCard and Account</p>

<pre><code>    #pragma once

    #include&lt;string&gt;

    class CreditCard
    {
    private:
        std::string number;
        int expMonth;
        int expYear;
        int pin;
    public:

        CreditCard():number(""), expMonth(0), expYear(0), pin(0)
        {

        }

        CreditCard(std::string number, int expMonth, int expYear,int pin):number(number), expMonth(expMonth), expYear(expYear), pin(pin)
        {
            if(number.length()!=5)
            {
                throw std::invalid_argument("Card number must be 5 characters");
            }
            if(expMonth&lt;0 || expMonth&gt;12)
            {
                throw std::invalid_argument("Invalid expiration month");
            }
            if(expYear&lt;2014 || expYear&gt;2020)
            {
                throw std::invalid_argument("Invalid expiration year");
            }
            if(pin&lt;1000 || pin&gt;9999)
            {
                throw std::invalid_argument("PIN must be between 1000 and 9999");
            }
        }

        CreditCard(const CreditCard &amp;creditCard):number(creditCard.number), expMonth(creditCard.expMonth), expYear(creditCard.expYear), pin(creditCard.pin)
        {

        }   

        CreditCard(CreditCard &amp;&amp;creditCard):number(std::move(creditCard.number)), expMonth(std::move(creditCard.expMonth)), expYear(std::move(creditCard.expYear)), pin(std::move(creditCard.pin))
        {
            creditCard.number="";
            creditCard.expMonth=0;
            creditCard.expYear=0;
            creditCard.pin=0;
        }

        CreditCard&amp; operator = (const CreditCard &amp;creditCard)
        {
            number=creditCard.number;
            expMonth=creditCard.expMonth;
            expYear=creditCard.expYear;
            pin=creditCard.pin;
            return *this;
        }

        CreditCard&amp; operator = (CreditCard &amp;&amp;creditCard)
        {
            if(this!=&amp;creditCard)
            {
                number=std::move(creditCard.number);
                expMonth=std::move(creditCard.expMonth);
                expYear=std::move(creditCard.expYear);
                pin=std::move(creditCard.pin);
                number=creditCard.number;
                expMonth=creditCard.expMonth;
                expYear=creditCard.expYear;
                pin=creditCard.pin;
            }
            return *this;
        }

        std::string getNumber() const
        {
            return number;
        }

        int getExpMonth() const
        {
            return expMonth;
        }

        int getExpYear() const
        {
            return expYear;
        }

        int getPin() const
        {
            return pin;
        }
    };


#pragma once

#include&lt;string&gt;
#include"CreditCard.h"

class Account
{
private:
    std::string number;
    float amount;
    CreditCard creditCard;
public:
    Account():number(""), amount(0), creditCard()
    {

    }

    Account(std::string number, float amount, CreditCard creditCard) : number(number), amount(amount), creditCard(creditCard)
    {

    }

    Account(const Account &amp;account) : number(account.number), amount(account.amount), creditCard(account.creditCard)
    {

    }

    Account(Account &amp;&amp;account) : number(std::move(account.number)), amount(std::move(account.amount)), creditCard(std::move(creditCard))
    {

    }

    Account&amp; operator = (const Account &amp;account)
    {
        number=account.number;
        amount=account.amount;
        creditCard=account.creditCard;      
        return *this;
    }

    Account&amp; operator = (Account &amp;&amp;account)
    {
        if(this!=&amp;account)
        {
            number=account.number;
            amount=account.amount;
            creditCard=account.creditCard;

            account.number="";
            account.amount=0;
            account.creditCard=CreditCard("",0,0,0);
        }
        return *this;
    }

    std::string getNumber() const
    {
        return number;
    }

    float getAmount() const
    {
        return amount;
    }

    void deposit(const float &amp;depositAmount)
    {
        amount+=depositAmount;
    }

    void withdraw(const float &amp;withdrawAmount)
    {
        amount-=withdrawAmount;
    }
};
</code></pre>

<p>And in main i have this line:</p>

<pre><code>Account account1("x12345x",1235.2, CreditCard("12345",1,2014,1122));
</code></pre>

<p>What is happening:</p>

<ol>
<li>CreditCard constructor gets called</li>
<li>CreditCard move constructor gets called</li>
<li>Account constructor gets called</li>
<li>CreditCard copy constructor gets called</li>
</ol>

<p>I don't understand why 4 is happening. Why that copy constructor call?</p>

<p>PS:Any correction regarding those classes is appreciated.</p>
