C++ Product Code Reader

riceball

Hi guys, I'm fairly new at programming and I've worked on a project with my friend that I'm attempting to convert to C++ from C#, as that's his native language and he suggested I try to convert it for practice, as my studies require C++.

This is the original C# code:

 
 
 
 
using System;
 
 
using System.Collections.Generic;
 
 
using 
 
 
System.Linq;
 
 
using System.Text;
 
 
 
 
 
 
 
 
namespace UPC
 
 
{
 
 
    class Program
 
 
 
 
 
{
 
 
        static void Main(string[] 
 
 
args)
 
 
 
 
 
{
 
 
 
 
 
checkCode("076281703220"); //12 numbers representing upc 
 
 
code
 
 
        }
 
 
 
 
 
 
 
 
        private static void 
 
 
checkCode(string code)
 
 
 
 
 
{
 
 
            int 
 
 
total = 0;
 
 
 
 
 
for (int i = 0; i < code.Length; 
 
 
i++)
 
 
 
 
 
{
 
 
 
 
 
Console.WriteLine(code.Substring(i, 1) + " rest:" + i % 2); //test ( if rest 
0 
 
 
multiply value by 3 if rest 1 take value(multiply by 
 
 
1)
 
 
 
 
 
if (i % 2 == 
 
 
1)
 
 
 
 
 
{
 
 
 
 
 
Console.WriteLine("added" + Int32.Parse(code.Substring(i, 1)));// 
 
 
test
 
 
 
 
 
total += Int32.Parse(code.Substring(i, 1)); //rest = 1 so add 
 
 
value
 
 
 
 
 
}
 
 
 
 
 
else
 
 
 
 
 
{
 
 
 
 
 
Console.WriteLine("added" + (Int32.Parse(code.Substring(i, 1)) * 3));  
 
 
//test
 
 
 
 
 
total += (Int32.Parse(code.Substring(i, 1)) * 3); // rest = 3 so add 
 
 
value*3                    
 
 
 
 
 
 
 
 
}
 
 
 
 
 
}
 
 
 
 
 
Console.WriteLine(total);
 
 
 
 
 
if (total % 10 == 0) //correct 
 
 
UPC
 
 
 
 
 
{
 
 
 
 
 
Console.WriteLine("UPC IS 
 
 
OK");
 
 
 
 
 
}
 
 
 
 
 
Console.ReadLine();
 
 
 
 
 
}
 
 
    }
 
 
}

This is the code that I've come up with after converting it to the best of my ability (with some help):

#include <iostream> 
#include <string>
using namespace std;
void checkCode(string code)
 
{
        int total = 0;
        for (int i(0); i<code.length(); i++)
        {
                cout << code.substr(i,1) << " rest: " << i %2 << endl;
                if (i % 2 == 1)
                {
                        cout << " added " << code.substr(i,1) << endl;
                        total += atoi(code.substr(i,1).c_str());
                }
 
                else
                {
                        cout << " added " << atoi(code.substr(i,1).c_str()) * 3 << endl;
                        total += (atoi(code.substr(i,1).c_str()) * 3);
                }
        }
 
        cout << total;

        if (total % 10 == 0)
 
        {
                cout << "UPC IS OK" << endl;
        }
        cin >> total;
 
}
 
 
 
int main ()
{
 checkCode("076281703220"); 
}

My problem is this (and I'm assuming it's fairly an easy fix) -- I need a more efficient way to take say, 15 or 20 product codes, so do I just copypaste this: checkCode("076281703220"); however many times I need to in the main method to check whichever codes I need to?

Also, it says I have an error and that atoi is not defined within the scope. Any help is appreciated.

srsly78

You need to include the right header to use atoi: #include <stdlib.h>

For the codes you should put them in an xml file, then read that in. There are many xml libraries for c++, I use one called Xerces. Failing that a simple list of items seperated by newlines can be easily read manually.