sortstocks.cpp

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#include <iostream>
#include <fstream>
#include <string>
#include <iomanip>
using namespace std;

#include "tvector.h"
#include "strutils.h"  // for atoi and atof
#include "prompt.h"
#include "sortall.h"
#include "stock.h"

struct PriceComparer   // compares using price
{
    int compare(const Stock& lhs, const Stock& rhs) const
    {   if (lhs.price < rhs.price) return -1;
	    if (lhs.price > rhs.price) return +1;
	    return 0;
    }
};
struct VolumeComparer  // compares using volume of shares traded
{
    int compare(const Stock& lhs, const Stock& rhs) const
    {   if (lhs.shares < rhs.shares) return -1;
	    if (lhs.shares > rhs.shares) return +1;
	    return 0;
    }
};

void Read(tvector<Stock>& list, const string& filename)
// post: stocks from filename read into list
{
    ifstream input(filename.c_str());
    string symbol, exchange, price, shares;
    while (input >> symbol >> exchange >> price >> shares)
    {   list.push_back(Stock(symbol,exchange,atof(price),atoi(shares)));
    }
}

void Print(const tvector<Stock>& list, ostream& out)
// post: stocks in list printed to out, one per line
{
    int k,len = list.size();
    out.precision(3);        // show 3 decimal places
    out.setf(ios::fixed);
    for(k=0; k < len; k++)
    {   out  << list[k].symbol << "\t" << list[k].exchange << "\t"
             << setw(8) << list[k].price << "\t" << setw(12)
             << list[k].shares << endl;
    }
}
int main()
{
    string filesymbol = PromptString("stock file ");
    tvector<Stock> stocks;
    Read(stocks,filesymbol);
    Print(stocks,cout);
    cout << endl << "----" << endl << "# stocks: " << stocks.size() << endl;
    cout << "----sorted by price----" << endl;
    InsertSort(stocks,stocks.size(), PriceComparer());
    Print(stocks,cout);
    cout << "----sorted by volume----" << endl;
    InsertSort(stocks,stocks.size(), VolumeComparer());
    Print(stocks,cout);
    return 0;
}