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virtual function()

BasicNewbie (145)
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#include <iostream>
#include <string>

using namespace std;

class A{
private:
	string AFood;

public:

	A( string theAFood){
		AFood = theAFood;
	}
	virtual void displayFoodType() const{

	}

	virtual string getAFood() const {
		return AFood;
	}
};

class B : public A{
private:
	string BFood;

public:
	B( string theBFood , string theAFood ) : A( theAFood ){
		BFood = theBFood;
	}

	virtual string getBFood() const{
		return BFood;
	}

	virtual void displayFoodType() const{
		cout << "---------------------\nA is for " << getAFood() << "\nB is for " << getBFood() << endl;
	}
};

class C : public B{
private:
	string CFood;

public:
	C( string theCFood , string theBFood , string theAFood ) : B( theBFood , theAFood ){
		CFood = theCFood;
	}

	virtual string getCFood() const {
		return CFood;
	}

	virtual void displayFoodType() const{
		cout << "---------------------\nA is for " << getAFood() << "\nB is for " << getBFood() << "\nC is for " << getCFood() << endl;
	}
};

int main(){

	B B1( "Burger" , "Avocado" );
	B B2( "Bean " , "Acorn" );

	C C1( "Cheese" , "Blueberry" , "Almond" );
	C C2( "Cherry" , "Banana" , "Apple" );

	cin.get();
	return 0;
}


Output should be :
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A is for Acorn
B is for Bean
---------------------
A is for Almond
B is for Blueberry
C is for Cheese


How should i implement it to using the virtual function? tried it but keep fail , because yesterday only learn , hard to get it , pass by constructor i think mine is correct already

so whats my error ?
Peter87 (11178)
To get that output you need to call the displayFoodType function.
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B2.displayFoodType();
C1.displayFoodType();
BasicNewbie (145)
You should check that appropriate foods do begin with the correct letter.


The display I done it , sorry for didn't updated 
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B1.displayFoodType();
	B2.displayFoodType();
	C1.displayFoodType();
	C2.displayFoodType();


but now i have to declare a function that if my instance object , that for AFood is not start with letter 'A' or 'a' , the constructor won't pass it , same to BFood and CFood , BFood must start with case 'b' or 'B' if not it won't pass to constructor and wont out the statement

example i insert

C C1( "Cheese" , "Clueberry" , "Diamond" );

so the output will be:

C is for Cheese

B and A won't come out since it's not begin with the letter b and a
JellyFox (35)
Declaring a function virtual only makes a difference if you access it through a pointer or a reference to the object. In your case, you're accessing your objects directly, so it doesn't matter whether or not the functions are virtual.
BasicNewbie (145)
cant get what u mean . so mean cn i do it?
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