I'm trying to sort for the top and second top value of totalRevenue
and its name
. I've tried to sort them in descending order this way but I could not figure it out how to make it work. Can anyone please help me out? First two entries:
1002 Hammer 23.65 203
1024 Nails 6.95 400
Here is the code:
#include <iostream>
#include <string>
#include <fstream>
using namespace std;
// Structure to hold statistics
struct Selling {
int productNumber;
string name;
double price;
int soldNumber;
double totalRevenue[];
};
int main()
{
ifstream statFile;
string productName;
double price;
int productNumber, soldNumber;
Selling *productArray[100];
Selling *aSelling;
int numProduct = 0;
int man = 0;
statFile.open("sales.txt");
while (numProduct < 100 && statFile >> productNumber >> productName >> price >> soldNumber)
{
Selling *aSelling = new Selling;
aSelling->productNumber = productNumber;
aSelling->name = productName;
aSelling->price = price;
aSelling->soldNumber = soldNumber;
aSelling->totalRevenue[] = aSelling->price * aSelling->soldNumber;
productArray[numProduct++] = aSelling;
//cout << aSelling->productNumber<< " " << aSelling->name << " " << aSelling->price << " " << aSelling->soldNumber << " " << aSelling->totalRevenue << endl;
}
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5; j++) {
if (aSelling->totalRevenue[i] > aSelling->totalRevenue[j]) {
man = aSelling->totalRevenue[i];
aSelling->totalRevenue[i] = aSelling->totalRevenue[j];
aSelling->totalRevenue[i] = man;
}
}
}
for (int i = 0; i < 2; i++) {
cout << "The top selling product is " << aSelling->name << "with total sales of " << aSelling->totalRevenue[i] << endl;
cout << "The second top selling product is " << aSelling->name << "with total sales of " << aSelling->totalRevenue[i - 1] << endl;
}
}
And there is an unexpected expression error at the line aSelling->totalRevenue[] = aSelling->price * aSelling->soldNumber;
which I don't understand.
There is some confusion on the arrays to sort:
totalRevenue
as a double
, not an array of doubles,numProduct
elements of the array productArray
based on the criteria totalRevenue
and name
, the order is determined by the comparison operator used. Only compare the second criteria if the first criteria give equal values.Here is a modified version:
#include <iostream>
#include <string>
#include <fstream>
using namespace std;
// Structure to hold statistics
struct Selling {
int productNumber;
string name;
double price;
int soldNumber;
double totalRevenue;
};
int compareSellings(const Selling *a, const Selling *b) {
// sort in decreasing order of totalRevenue
if (a->totalRevenue > b->totalRevenue) return -1; // a comes before b
if (a->totalRevenue < b->totalRevenue) return +1; // b comes before a
// sort in increasing order of name for the same totalRevenue
if (a->name < b->name) return -1; // a comes before b
if (a->name > b->name) return +1; // b comes before a
return 0;
}
int main() {
ifstream statFile;
string productName;
double price;
int productNumber, soldNumber;
Selling *productArray[100];
int numProduct = 0;
statFile.open("sales.txt");
while (numProduct < 100 && statFile >> productNumber >> productName >> price >> soldNumber) {
Selling *aSelling = new Selling;
aSelling->productNumber = productNumber;
aSelling->name = productName;
aSelling->price = price;
aSelling->soldNumber = soldNumber;
aSelling->totalRevenue = price * soldNumber;
productArray[numProduct++] = aSelling;
//cout << aSelling->productNumber<< " " << aSelling->name << " "
// << aSelling->price << " " << aSelling->soldNumber << " "
// << aSelling->totalRevenue << endl;
}
for (int i = 0; i < numProduct; i++) {
for (int j = 0; j < numProduct; j++) {
if (compareSellings(productArray[i], productArray[j]) > 0) {
Selling *aSelling = productArray[i];
productArray[i] = productArray[j];
productArray[j] = aSelling;
}
}
}
cout << "The top selling product is " << productArray[0]->name
<< ", with total sales of " << productArray[0]->totalRevenue << endl;
cout << "The second selling product is " << productArray[1]->name
<< ", with total sales of " << productArray[1]->totalRevenue << endl;
return 0;
}
Further remarks:
<algorithms>
and dynamic arrays of objects instead of allocating the objects with new
and manipulating naked pointers.
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