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    <p>Hmm...I think there's a <em>lot</em> easier way to handle this:</p> <pre><code>class animal { static int count; animal() { ++count; } ~animal() { --count; } }; class horse : public animal { // horse stuff }; class pig : public animal { // pig stuff here }; class dog : public animal { // dog stuff here }; int patient_count() { return animal::count; } </code></pre> <p>Other than that, your code seems to have a fairly basic problem: it's confusing (for example) an animal with a collection of animals. You have a number of things like:</p> <pre><code>dog current_dog; // Create a instance // Send 3 values to the object current_dog.add_dog("Misty, 15, Female"); current_dog.add_dog("Tristian, 12, Male"); current_dog.add_dog("Tempest, 11, Female"); </code></pre> <p>This makes no sense. A dog should represent exactly that: one dog. It has one name, one age, one sex, and so on. What you have above is really three dogs, not one. To represent them, you should have a collection of dogs -- preferably a standard collection like <code>std::vector</code>, but if you're not allowed to use that (which may be semi-reasonable, since this sounds/seems like homework) at least an array.</p> <pre><code>dog dogs[10]; // an array of 10 dogs (none yet initialized though) dogs[0] = dog("Misty, 15, female"); dogs[1] = dog("Tristian, 12, male"); dogs[2] = dog("Tempest, 11, female"); </code></pre> <p>Pigs, cows, horses, etc., are pretty much the same: one animal object should represent one actual animal. A collection of animals is a different thing from a single animal. Note, however, the comment above: an array of 10 dogs is exactly that -- 10 dogs (even though none of them has a name, age or sex yet, we've defined them so they all officially exist). This means the <code>patient_count</code> will report the existence of 10 dogs when you define the array, regardless of the number that contain meaningful data. This is one way in which <code>std::vector</code> is clearly a better choice. If you do something like:</p> <pre><code>std::vector&lt;dog&gt; dogs; dogs.push_back("Misty, 15, female"); dogs.push_back("Tristian, 12, male"); dogs.push_back("Tempest, 11, female"); </code></pre> <p>At this point, you've created and stored 3 dogs, so if you print out <code>patient_count</code> at this point, it should show 3 (representing actual dogs created/defined) not 10 (or whatever) to represent the number of <em>potential</em> animals, while ignoring the number that contain meaningful data.</p>
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    1. POCreating a function that is a friend to multiple classes
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    1. USJerry Coffin
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    1. COUpvoting because you explain the dog/collection-of-dog issue with OP's code, but your `count()` is going to be giving some pretty inconsistent answers depending on how many temporary instances of dogs/pigs/horses happen to be live when you ask for the count.
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      1. USLambdageek
    2. CO@Lambdageek: I'm not sure "inconsistent" is the word I'd use -- you're certainly right that the number of objects at a given point in time may not match the number the user thinks s/he has created. At the same time, what it reports *should* be consistent with the number that actually exist.
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      1. USJerry Coffin
    3. COThanks for the info. I am working on the solution now, I will comment on which one I can make work. BTW I tried the overloading solution before I asked the question. I created 3 versions of the function each expecting to be passed a structure from a different class. I like the Sub classing solution right now the best it seems the most logical, I will try it first.
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      1. USNicole Cook
 

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