Class question

[jackpoophard]

#include<iostream>

#include<string>

using namespace std;


class fish
{
public:

fish(string name);

void swim();
void eat();


protected:
string Name;
};

class cow:public fish
{
public:
cow(string name);
void sleep(int count);
};

fish::fish(string name)
{
name = Name;
}

void fish::swim()
{
cout << Name << "just learned how to swim" << endl;
}

void fish::eat()
{
cout << Name << "just learned how to eat" << endl;
}

void cow::sleep(int count)
{
cout << Name << "just slept for " << count << " times, YOU LOSE!" << endl;
}

int main()
{
fish Fish("FISH");
cow Cow("COW");

char a;

cout << "U wanna play (y/n)" << endl;
cin >> a;

if(a == 'y' || a == 'Y')
{
cout << "Ok sweet" << endl;
}
else
{
cout << "WTH" << endl;
cin.get();
return 1;
}
cout << "Pick a number" << endl;
short int b;
cin >> b;

cout << "Ok here's how you play, you have a pet and let's see if you win or lose" << endl;

Fish.swim();
Fish.eat();
Cow.sleep(b);

cout << "Done" << endl;
cin.get();
return 0;
}

I dunno why but apparently this is the problem:

[Linker error] undefined reference to `cow::cow(std::string)'
ld returned 1 exit status '

[firedraco]

In class cow you have:

cow(string name);

But you never define it anywhere.

Btw, to use code tags, you put them around all your code, not just the keywords and stuff.

[jackpoophard]

Hmm..how should I define it?

[blackcoder41]

that's funny a cow inherits from a fish ^^
first please fix your code, http://cplusplus.com/articles/firedraco1/

you should implement it like this..

cow::cow(string name) {
  Name = name;
}

[blackcoder41]

woah i think this is wrong..

fish::fish(string name)
{
  name = Name;
  //shouldn't it be
  //Name = name; ?
}

[jackpoophard]

K i did that and this problem shows up:

cow::cow(string name) {
Name = name;
}


C:\Dev-Cpp\Untitled1.cpp In constructor `cow::cow(std::string)':


and this "32 C:\Dev-Cpp\Untitled1.cpp no matching function for call to `fish::fish()' " is for:

fish::fish(string name)
{
Name = name;
}

[blackcoder41]

#include<iostream>
#include<string>

using namespace std;

class fish {
 public:
    fish();
    fish(string name);
    void swim();
    void eat();

 protected:
    string Name;
};

class cow : public fish {
 public:
    cow(string name);
    void sleep(int count);
};

fish::fish() {
}

fish::fish(string name) {
    fish::Name = name;
}

void fish::swim() {
    cout << Name << " just learned how to swim" << endl;
}

void fish::eat() {
    cout << Name << " just learned how to eat" << endl;
}

cow::cow(string name) : fish(name) {
}

void cow::sleep(int count) {
    cout << Name << " just slept for " << count << " times, YOU LOSE!" << endl;
}

int main() {
    fish Fish("FISH");
    cow Cow("COW");

    char a;

    cout << "U wanna play (y/n)" << endl;
    cin >> a;

    if(a == 'y' || a == 'Y') {
        cout << "Ok sweet" << endl;
    } else {
        cout << "WTH" << endl;
        cin.get();
        return 1;
    }
    cout << "Pick a number" << endl;
    short int b;
    cin >> b;

    cout << "Ok here's how you play, you have a pet and let's see if you win or lose" << endl;

    Fish.swim();
    Fish.eat();
    Cow.sleep(b);

    cout << "Done" << endl;
    cin.get();
    return 0;
} 

[tummychow]

Aw man, don't just solve the problem....

[blackcoder41]

@tummychow
sorry, i didn't mean to.. it's just his code above is hard to read.

so here's how it works.
by default a derive class calls the the default constructor (constructor w/o param) of the base class. so in this case the base class fish doesn't have a default constructor so we explicitly have to call the constructor with string parameters in line 38;

please read more.. http://cplusplus.com/doc/tutorial/inheritance/

[yoked88]

lol Funniest thig I've seen all day!!

that's funny a cow inherits from a fish ^^
first please fix your code, http://cplusplus.com/articles/firedraco1

I was confused too, but after I read this I just laughed and forgot about it; good times.

[blackcoder41]

haha. yeah me too ^^
IMO it is very funny! ; )

[yoked88]

lol does that mean the cow can swim and eat?? lol swimming cows....
OMG I"m still laughing at this....

[yoked88]

lol....I'm bored does this code accomplish anything?
I'm having a hard time understanding because I'm a noob :(
Apparently you lose no matter what???
Still funny though lol

[blackcoder41]

hey me too, i'm a n00b and i'm bored.. hey do you like game programming? maybe we could make a n00b team.

[yoked88]

Well actually, Game Software Development is my major and I'm just getting into my 3rd week of programming so as soon as I have a good handle on data manipulation; I just started learning classes...