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1st class lever
Laurice vielle Melay...
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∙ 9y agolever.
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Who invented the machine that makes egg cartons?
John huntsman
Describe a chicken using a programming language?
chicken is a function which takes argument as grain type and returns egg. egg chicken(grain x);
What do you mean by forward declarations of a class in c plus plus?
Which came first, the chicken or the egg? The answer is, of course, the egg. After all, birds evolved long after egg-laying reptiles, so eggs had to have come first. But what exactly does that have to do with forward declarations? Well, everything, as it turns out. Forward declarations are essential whenever two classes depend on each other.As you know, in C++ you must define a type before you can use it. So let's define a simple chicken and egg:#include class Chicken{public:Chicken(Chicken* parent=0):m_pParent(parent){}Egg* lay_egg();private:Chicken* m_pParent;};class Egg{public:Egg(Chicken* parent=0): m_pParent(parent){}Chicken* hatch();private:Chicken* m_pParent;};Egg* Chicken::lay_egg(){return(new Egg(this));}Chicken* Egg::hatch(){return(new Chicken(m_pParent));}int main(){Chicken chicken;Egg* egg = chicken.lay_egg();Chicken* chick = egg->hatch();Egg* egg2 = chick->lay_egg();delete(egg2);egg2=0;delete(chick);chick=0;delete(egg);egg=0;return(0);}Straight away there's a problem. The compiler won't allow this because our chicken lays eggs but the definition of an egg appears after the definition of a chicken. Ah, but of course -- eggs came first! So let's swap the definitions around:#include class Egg{public:Egg(Chicken* parent=0): m_pParent(parent){}Chicken* hatch();private:Chicken* m_pParent;};class Chicken{public:Chicken(Chicken* parent=0):m_pParent(parent){}Egg* lay_egg();private:Chicken* m_pParent;};Egg* Chicken::lay_egg(){return(new Egg(this));}Chicken* Egg::hatch(){return(new Chicken(m_pParent));}int main(){Chicken chicken;Egg* egg = chicken.lay_egg();Chicken* chick = egg->hatch();Egg* egg2 = chick->lay_egg();delete(egg2);egg2=0;delete(chick);chick=0;delete(egg);egg=0;return(0);}Hmm. The compiler's still not happy. Our eggs need to hatch chickens but, again, the definition of a chicken now appears after the definition of an egg. We seem to have a catch-22 situation. No matter which order we define them, we simply cannot emulate a simple chicken and an egg.The answer is, you guessed it, to use a forward declaration:#include class Chicken; // forward declaration!class Egg{public:Egg(Chicken* parent=0): m_pParent(parent){}Chicken* hatch();private:Chicken* m_pParent;};class Chicken{public:Chicken(Chicken* parent=0):m_pParent(parent){}Egg* lay_egg();private:Chicken* m_pParent;};Egg* Chicken::lay_egg(){return(new Egg(this));}Chicken* Egg::hatch(){return(new Chicken(m_pParent));}int main(){Chicken chicken;Egg* egg = chicken.lay_egg();Chicken* chick = egg->hatch();Egg* egg2 = chick->lay_egg();delete(egg2);egg2=0;delete(chick);chick=0;delete(egg);egg=0;return(0);}Now the code compiles!The forward declaration simply acts as a sort of place-holder. We're just telling the compiler that although we aren't quite ready to define a chicken, one will be defined at some point -- it may even be in a completely different file. But that is enough to appease the compiler, it can simply fill in the blanks when our chicken is fully defined.This type of scenario crops up quite a lot, especially when working with parent and child classes that must depend on each other, just like our chicken and egg. However, we normally design our classes using separate source files each with their own header file, and that would then make it impossible for our chicken and egg header's to include each other's header. Instead, we must use forward declarations in the headers, and place the corresponding #include directives in the source files.
How can i build an Egg Drop involving Only Toothpicks and Glue and without breaking the egg?
You can glue toothpicks in layers around the egg then make a container for the egg to go in.Also, you can put super glue around the egg.I think if you did this your egg would withstand the fall.
How do you make a catapult to launch an egg?
you put an egg in a cannon and shoot itweeniers
What is an Egg Slicer aluminum?
Its an aluminum egg slicer
How do you make an egg cracking machine out simple machines?
how do you make a simple machine
A thing in the kitchen that starts with the letter E?
· eggs · egg timer · espresso machine
Is egg beater a simple machine?
yes it is a lever
What kind of simple machine is an egg beater?
A rotary device
What is a simple machine that has a wheel and axel that turn togethet?
maybe in a kitchen you have a egg spinner
Is an egg carton a simple machine?
Simple yes but effective. It is simple in comparrison to othe machines such as a car or computer etc. which is bigger and more confuzing!!
Can anyone give you some examples of Convenience baking tools or equipments?
egg slicer
Is an egg carton a machine?
Simple yes but effective. It is simple in comparrison to othe machines such as a car or computer etc. which is bigger and more confuzing!!
What are some kitchen items that with the letter e?
* Eggs* Egg beater * Egg slicer * Egg ring * Egg separator * Egg cooker * Egg poacher* Easy bake oven * Espresso machineegg beater...? is that real?
Kitchen ware that start with E?
* egg timer * egg slicer * egg poacher * egg cooker * electric oven * electric skillet * electric wok * electric griddle * electric can opener * egg beater * egg separator
What are some kitchen items that begin with the letter E?
* Eggs* Egg beater * Egg slicer * Egg ring * Egg separator * Egg cooker * Egg poacher* Easy bake oven * Espresso machineegg beater...? is that real?
