stocks.cpp

// beginning of stocks.cpp file
#include <iostream>
#include <cstring>

class Stock
{
private:
	char company[30];
	int shares;
	double share_val;
	double total_val;
	void set_tot();
public:
	void acquire(const char * co, int n, double pr);
	void buy(int num, double price);
	void sell(int num, double price);
	void update(double price);
	void show();
}; // note semicolon at the end of a class

inline void Stock::set_tot()				// use inlien in defintion
{
	total_val = shares * share_val;
}

// more stocks.cpp -- implementing the class member functions
void Stock::acquire(const char * co, int n, double pr)
{
	std::strncpy(company, co, 29);			// truncate co to fit company
	company[29] = '\0';
	if (n < 0) 
	{
		std::cerr << "Number of shares can't be negative. "
			<< company << " shares set to 0.\n";
		shares = 0;
	} else {
		shares = n;
	}
	share_val = pr;
	set_tot();
}

void Stock::buy(int num, double price)
{
	if (num < 0)
	{
		std::cerr << "Number of shares purchased can't be negative. "
			<< "Transaction is aborted.\n";
	} else {
		shares += num;
		share_val = price;
		set_tot();	
	}
}

void Stock::sell(int num, double price)
{
	using std::cerr;
	if (num < 0) {
		cerr << "Number of shares sold cannot be negative. "
			<< "Transaction is aborted.\n";
	} else if (num > shares) {
		cerr << "You can't sell more than you have! "
			<< "Transaction is aborted.\n";
	} else {
		shares -= num;
		share_val = price;
		set_tot();
	}
}

void Stock::update(double price)
{
	share_val = price;
	set_tot();
}

void Stock::show()
{
	using std::cout;
	using std::endl;
	cout << "Company: " << company
		<< " Shares: " << shares << endl
		<< " Shares Price: $" << share_val
		<< " Total Worth: $" << total_val << endl;
}

int main()
{
	using std::cout;
	using std::ios_base;
	Stock stock1;
	stock1.acquire("NonoSmart", 20, 12.50);
	cout.setf(ios_base::fixed);
	cout.precision(2);
	cout.setf(ios_base::showpoint);
	stock1.show();
	stock1.buy(15, 18.25);
	stock1.show();
	stock1.sell(400, 20.00);
	stock1.show();
	return 0;
}