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stock20.h
// stock20.h -- augmented version
#ifndef STOCK20_H_
#define STOCK20_H_
#include <string>
#include<iostream>
class Stock
{
private:
char* str;
int shares;
double share_val;
double total_val;
void set_tot()
{
total_val = shares * share_val;
}
public:
Stock(); // default constructor
// Need to reconstruct constructor
// based on usestock2.cpp, neither need to overload operator=,
// nor create copy constructor
Stock(const char* c, long n = 0, double pr = 0.0);
~Stock(); // do-nothing destructor
void buy(long num, double price);
void sell(long num, double price);
void update(double price);
const Stock & topval(const Stock & s) const;
friend std::ostream& operator<<(std::ostream& os, const Stock& obj);
};
#endif
stock20.cpp
// stock20.cpp -- augmented version
#include <iostream>
#include "stock20.h"
using namespace std;
// constructors
Stock::Stock() // default constructor
{
shares = 0;
share_val = 0.0;
total_val = 0.0;
}
Stock::Stock(const char* c, long n, double pr)
{
// Newly added:
int len = strlen(c) + 1;
str = new char[len];
strcpy_s(str, len, c);
if (n < 0)
{
std::cout << "Number of shares can't be negative; "
<< *str << " shares set to 0.\n";
shares = 0;
}
else
shares = n;
share_val = pr;
set_tot();
}
// class destructor
Stock::~Stock() // quiet class destructor
{
}
// other methods
void Stock::buy(long num, double price)
{
if (num < 0)
{
std::cout << "Number of shares purchased can't be negative. "
<< "Transaction is aborted.\n";
}
else
{
shares += num;
share_val = price;
set_tot();
}
}
void Stock::sell(long num, double price)
{
using std::cout;
if (num < 0)
{
cout << "Number of shares sold can't be negative. "
<< "Transaction is aborted.\n";
}
else if (num > shares)
{
cout << "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();
}
const Stock & Stock::topval(const Stock & s) const
{
if (s.total_val > total_val)
return s;
else
return *this;
}
// Newly added
std::ostream& operator<<(std::ostream& os, const Stock& obj)
{
using std::ios_base;
// set format to #.###
ios_base::fmtflags orig =
os.setf(ios_base::fixed, ios_base::floatfield);
std::streamsize prec = os.precision(3);
os << "Company: " << obj.str
<< " Shares: " << obj.shares << '\n';
os << " Share Price: $" << obj.share_val;
// set format to #.##
os.precision(2);
os << " Total Worth: $" << obj.total_val << '\n';
// restore original format
os.setf(orig, ios_base::floatfield);
os.precision(prec);
return os;
}
main
// usestok2.cpp -- using the Stock class
// compile with stock20.cpp
#include <iostream>
#include "stock20.h"
const int STKS = 4;
int main()
{
{
// create an array of initialized objects
Stock stocks[STKS] =
{
Stock("NanoSmart", 12, 20.0),
Stock("Boffo Objects", 200, 2.0),
Stock("Monolithic Obelisks", 130, 3.25),
Stock("Fleep Enterprises", 60, 6.5)
};
std::cout << "Stock holdings:\n";
int st;
for (st = 0; st < STKS; st++)
std::cout << stocks[st];
// set pointer to first element
const Stock * top = &stocks[0];
for (st = 1; st < STKS; st++)
top = &top->topval(stocks[st]);
// now top points to the most valuable holding
std::cout << "\nMost valuable holding:\n";
std::cout << *top;
}
std::cin.get();
return 0;
}