Functions Problem

[treuss]

You are still not using a function. You use a return statement, you have no function except main to return from. Your book or lecture notes must have an example for a function. Read it. Understand it. Then look again at Post #3 above.

You are still having a condition while (target != SENTINEL) but don't change either value in the loop. The condition can thus be only "always true" or "always false" thus making little sense.

[Ruined Embrace]

After days and days of slaving, I think I finally have something that works. You guys see any corrections I could make to this?

#include <iostream>
#include <string>
#include <fstream>

using namespace std;

string findName(int parkingSticker);

int main ()
{
    int target = 0;
    const double SENTINEL = 000000;
    //string functionMessage = "";

    cout << "Please enter a parking sticker number (enter 000000 to exit): " << endl;
    cin >> target;
   
    while (target != SENTINEL)
    {
          if  (findName (target) == "NOT FOUND")
          {
              cout << "This parking sticker is not on file. Try again." << endl << endl;
          }
          else
          {
              cout << "This parking sticker belongs to " << findName(target) << endl << endl;   
          }
          
          cout << "Please enter a parking sticker number (enter 000000 to exit): " <<endl;
          cin >> target;   
    }
   
    system ("pause");
    return 0;
   
}

string findName (int parkingSticker)
{
    string name;
    int tempNum;
    string returnValue = "";
    ifstream input;
    input.open("HWK5.txt");  
   
    input >> name >> tempNum;
    while (!input.eof())
    {
            if (parkingSticker == tempNum)
            {
                      returnValue = name;
                      break;
            }                
            else if (parkingSticker != tempNum)
            {
                 input >> name >> tempNum;
               
            }   
    } 

    if (returnValue == "")
    {
        returnValue = "NOT FOUND";               
    }

    return returnValue;

}

[Paul McKenzie]

You guys see any corrections I could make to this?

Not corrections, but a misunderstanding of what a double means:

    const double SENTINEL = 000000;

Those extra 0's do nothing except wear out your keyboard. This is exactly the same as this:

const double SENTINEL = 0.0;

Why is SENTINEL a double anyway? Since target is an int, then SENTINEL should be an int.

Regards,

Paul McKenzie

[Ruined Embrace]

I'm not sure man. My professor is kind of strange. He demands we use const double SENTINEL = 000000

[treuss]

    input >> name >> tempNum;
    while (!input.eof())
    {
            if (parkingSticker == tempNum)
            {
                      returnValue = name;
                      break;
            }                
            else if (parkingSticker != tempNum)
            {
                 input >> name >> tempNum;
               
            }   
    }

A better way to write this would be:

    while (input >> name >> tempNum)
    {
            if (parkingSticker == tempNum)
            {
                      returnValue = name;
                      break;
            }                
    }

Another improvement I could think of would be to initialize returnValue with "NOT FOUND" and not with an empty string. This would save the check after the loop.

[laserlight]

I suppose that if you were not concerned about trying for a single point of return, the returnValue variable could be easily eliminated:

while (input >> name >> tempNum)
{
    if (parkingSticker == tempNum)
    {
        return name;
    }
}
return "NOT FOUND";