Simple Vector Problem

[tilt]

New to C++ and Programming in General. Have a quick question about my code.

//Legal Move Generator
void legal_move(vector<int> &move, position board[], int size);

//Generate Moves
void legal_move(vector<int> &move, position board[], int size){
	int counter = 0;
	for(counter; counter <= size; counter++){
		if(board[counter].occupied == 0){
			//Assign the value of counter to the vector move, and so on
		}
	}
}

I would just use an array in the function, but obviously the legal moves will grow and shrink, so I thought a vector would be a better fit. The question is in the comment under the if condition--

Thanks for any help.