$//$ This program nests one class inside another. It has a class

$//$ with a member variable that is an instance of another class.

#include

using namespace std;

class Rectangle

$\{$

private:

double length;

double width;

public:

void setLength$($double len$)$

$\{$ length $=$ len; $\}$

void setWidth$($double wid$)$

$\{$ width $=$ wid; $\}$

double getLength$()$

$\{$ return length; $\}$

double getWidth$()$

$\{$ return width; $\}$

double getArea$()$

$\{$ return length $*$ width; $\}$

$\}$;

class Carpet

$\{$

private:

double pricePerSqYd;

Rectangle size; $//$ size is an instance of

$//$ the Rectangle class

public:

void setPricePerYd$($double p$)$

$\{$ p $=$ pricePerSqYd; $\}$

void setDimensions$($double len, double wid$)$

$\{$ size.setLength$($len$)$;

size.setWidth $($wid$)$;

$\}$

double getTotalPrice$()$

$\{$ return $($size$.$getArea$()*$ size.getLength$())$; $\}$

$\}$;

$//**************$ Client Program $*****************$

int main$()$

$\{$

Carpet purchase; $//$ This variable is a Carpet object

double pricePerYd;

double length;

double length;

cout $<<$ "Room length in feet: $"$;

cin $>>$ length;

cout $<<$ "Room width in feet : $"$;

cin $>>$ width;

cout $<<$ "Carpet price per sq$.$ yard: $"$;

cin $>>$ pricePerYd;

purchase.setDimensions$($length$,$ width$)$;

purchase.setPricePerYd$($pricePerYd$)$;

cout $<<"$

The total price of my new $"<<$ length $<<"$ x $"<<$ width

$<<"$ carpet is $$"<<$ purchase.getTotalPrice$()<<$ endl;

return $0$;

$\}$