Too few arguments inheritance c++ -

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i'm working on learning inheritance making generic list class. list can unordered list, ordered list, stack, or queue.

my list class looks this:

class list { public:      class node     {     public:         int data;         node * next;         node(int data);     };      int sizeoflist = 0;     node * head = nullptr;     list::list();     virtual void get(int pos);     virtual void insert(int data);     virtual void remove(int pos);     virtual void list();     virtual int size(); };

my unordered list class looks this:

class unorderedlist : public list { public:     unorderedlist();      void get();     void insert(int data);     virtual void remove(); //takes no parameters because first item removed };

in main(), create array of lists this;

list * lists[8];

and make unordered list this:

lists[0] = new unorderedlist();

my question: lists[listnum]->get(); gives error

"too few arguments in function call"

because thinks trying call get() in listclass, want call unordered list's function get().

i feel must improve upon sam varshachik's answer - though totally correct.

class list { public:     virtual void get(int pos); }; class unorderedlist : public list { public:     void get(); };

note there 2 problems here - not one.

firstly signature of get(int) different get() - these two different methods, , compiler treat them such.
further have declared method list::get(int) virtual, have not done-so unorderedlist::get() - remember list object has no knowledge it's children - list * cannot understand details of unorderedlist.

consider example:

class list { public:     virtual void get(int pos); }; class unorderedlist : public list { public:     virtual void get(); //still error! };

in case, have made unorderedlist::get() virtual - won't help. list still has no knowledge of method.

the correct snippet follows: 

class list { public:     virtual void get(int pos);     virtual void get(); }; class unorderedlist : public list { public:     virtual void get(); //we can use now!     virtual void get(int pos); //this needed if intend override method };

in example list::get() virtual method - such call communicated correct-child intended.
possible because the parent class has been informed such method exists, , can over-ridden child classes.

[edit /]

as jonathanpotter stated in comments, pay attention fact virtual keyword needed if wish method called parent-pointer routed actual child object. , incur overhead.


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