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SOLVED

Muddobber (7)
SOLVED :)
Last edited on
Chervil (7320)
The error is at line 127,
 
 
    selectionSort(sales, MAX_ITEMS, prod);


The number of items which were read from the file is not 100, it is 5.

Change MAX_ITEMS to LineNum 
 
 
    selectionSort(sales, LineNum, prod);


Some of the other code seems over-complex. For example you might read from the file and get the number of lines like this:
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int getMenuFromFile(ifstream& infile, prodType sales[])
{
    string strLine = "";
    int j = 0;

    while (getline(infile, strLine))
    {
        istringstream ss(strLine);
        if ( ss >> sales[j].prodNum
                >> sales[j].prodName
                >> sales[j].prodPrice
                >> sales[j].numSold)
        {
            sales[j].prod =  sales[j].prodPrice * sales[j].numSold;
            j++;
        }
    }

    return j;
}

As a bonus, that also populates the prod field, removing the need for a separate table.
Chervil (7320)
For context, this is the original code:
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#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
using namespace std;

const int MAX_ITEMS = 100;


struct prodType
{
    int prodNum;
    string prodName;
    double prodPrice;
    int numSold;
    double prod;
};

int getLineNum()
{
    int number_of_lines = 0;
    string line;
    ifstream myfile("sales.txt");

    while (getline(myfile, line))
        ++number_of_lines;
    cout << "Number of lines in text file: " << number_of_lines << endl;

    return number_of_lines;
}

void getMenuFromFile(ifstream& infile, prodType sales[], int LineNum)
{
    string strLine = "";
    string strProdNum = "";
    string strProdName = "";
    string strProdPrice = "";
    string strNumSold = "";
    int LastEmptyPos;
    int j = 0;


    while (getline(infile, strLine) && (j < LineNum))
    {
        for (int i = 0; i < strLine.size(); i++)
            if (strLine[i] == ' ') LastEmptyPos = i;

        strProdNum = "";
        strProdNum = strProdNum.append(strLine);                        //Store product number
        stringstream(strProdNum) >> sales[j].prodNum;

        strProdName = "";
        strProdName = strProdName.append(strLine, LastEmptyPos - 20);        //Store product name
        stringstream(strProdName) >> sales[j].prodName;

        strProdPrice = "";
        strProdPrice = strProdPrice.append(strLine, LastEmptyPos - 8);    //Store product price
        stringstream(strProdPrice) >> sales[j].prodPrice;


        strNumSold = "";
        strNumSold = strNumSold.append(strLine, LastEmptyPos + 1, strLine.size() - LastEmptyPos); //Store number of units sold
        stringstream(strNumSold) >> sales[j].numSold;

        j++;
    }
}

void makeProd(prodType sales[], double prod[], int LineNum)
{
    for (int i = 0; i < LineNum; i++)
    {
        prod[i] = sales[i].prodPrice * sales[i].numSold;
    };
}

void selectionSort(prodType sales[], int LineNum, double prod[])
{
    int i, j, first;
    for (i = LineNum - 1; i > 0; i--)
    {
        first = 0;
        for (j = 1; j <= i; j++)
        {
            if (prod[j] > prod[i])
                first = j;
        }
        prodType temp = sales[first];
        sales[first] = sales[i];
        sales[i] = temp;
    }

}

void printStructMembers(prodType sales[])
    {
        cout << "The top selling product is " << sales[4].prodName << " with total sales of $" << sales[4].prodPrice * sales[4].numSold << endl;
        cout << "The second top selling product is " << sales[3].prodName << " with total sales of $" << sales[3].prodPrice * sales[3].numSold << endl;
        cout << "The third top selling product is " << sales[2].prodName << " with total sales of $" << sales[2].prodPrice * sales[2].numSold << endl;
        cout << "The fourth top selling product is " << sales[1].prodName << " with total sales of $" << sales[1].prodPrice * sales[1].numSold << endl;
        cout << "The lowest selling product is " << sales[0].prodName << " with total sales of $" << sales[0].prodPrice * sales[0].numSold << endl;
    }



int main()
{
    string strline;
    prodType sales[MAX_ITEMS];
    ifstream inFile("sales.txt");
    double prod[MAX_ITEMS];

    int LineNum = getLineNum();

    if (inFile.is_open())
    {
        getMenuFromFile(inFile, sales, LineNum);
    }

    else
    {
        cout << "Cannot open the input file." << endl;
    }

    inFile.close();

    makeProd(sales, prod, LineNum);

    selectionSort(sales, MAX_ITEMS, prod);

    printStructMembers (sales);

    return 0;
}

and the input file:
1002 Hammer 23.65 203
1024 Nails 6.95 400
1276 Screwdriver 13.95 251
1385 Elec_Drill 45.69 132
1462 Air_Filter 7.95 500

though the original code doesn't make any sense at all with that file, it requires a fixed-width layout a bit like this:
  1002 Hammer       23.65  203
  1024 Nails         6.95  400
  1276 Screwdriver  13.95  251
  1385 Elec_Drill   45.69  132
  1462 Air_Filter    7.95  500

Wading through all that took some time and effort. A word of thanks might have been nice, rather than just deleting everything as though it never happened.
Last edited on
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