LNK2019 error whenever I call a function

[DCV]

I have an assignment in which I am supposed to manage a linked list of "players" in a hockey "roster." That's not the issue... problem is, I'm trying to make the function in which a new player is added, and I can't even call it. It results in a LNK2019 error, "unresolved external error," and I have no idea where I'm going wrong. (no worries... I'm not asking you guys to complete my assignment, I just want to know why I can't call this function)

Specifically, here's what the compiler returns whenever I try to call the function:

1>main.obj : error LNK2019: unresolved external symbol "public: void __thiscall roster::addPlayer(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >,int,class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >)" (?addPlayer@roster@@QAEXV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@0H0@Z) referenced in function _main
1>C:\Users\Dan Visintainer\Documents\Visual Studio 2008\Projects\rosterlinkedlist2\Debug\rosterlinkedlist2.exe : fatal error LNK1120: 1 unresolved externals

Here's roster.h:

class roster
{
public:
	roster(void);//CTOR
	~roster(void);//DTOR
	void addPlayer(std::string first, std::string last, int number, std::string position);
private:
	int goals, goalsagainst;
};

Here's roster.cpp:

#include <iostream>
#include <string>
#include "roster.h"
using namespace std;

roster::roster(void)
{
	roster::goals=0;
	roster::goalsagainst=0;
}

roster::~roster(void)
{
}

void addPlayer(string first, string last, int number, string position)
{
	cout<<"The function was called!\n";
}

And here's main.cpp:

#include <iostream>
#include <string>
#include "roster.h"
using namespace std;

void main()
{
	roster mainlist;
	string input, first, last, position;
	int number=0, minutes=0, goals=0, goalsagainst=0;
	cout<<"CSCI 201 Project 2 - Linked List\n";
	while (input != "q")
	{
		cout<<"\nCommand? >> ";
		getline(cin,input);
		if (input == "ap")
		{
			cout<<"ADD PLAYER: Please enter the player's LAST NAME, then press ENTER:\n>> ";
			getline(cin,last);
			cout<<"FIRST NAME: >> ";
			getline(cin,first);
			cout<<"POSITION: >> ";
			getline(cin,position);
			cout<<"NUMBER: >> ";
			cin>>number;
			cout<<endl;
			mainlist.addPlayer(first, last, number, position);
		}
	}
}

All help greatly appreciated.

[Dave Sinkula]

void roster::addPlayer(string first, string last, int number, string position)
{
	cout<<"The function was called!\n";
}

[dkalita]

for compilation use
c++ main.cpp roster.cpp