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[C++] Problem with for-loop

I have a problem for my class, and I've run into a really weird problem.

So the problem is a travel expense problem, where I need to use a for-loop to ask the user a few questions, such as cost of hotel, cost of parking fee, cost of bridge toll.

So anyhow here's a snippet of my code:

Code:

#include <iostream>

using namespace std;



int main()

{

double dhotel, dmeal, dpark, dbridge, dmiles, dtemp = 0.0; 

        string scar; // Car name

        int iyear; // Car year

        string scolor; // Car color

        string smake; // Car make

        int i = 0;

        int iSize = 0;

        int iCounter = 0;



/* = = = = = = = = = = = = = = = = = = = = = = = = = = = =        */        

        cout << "Enter number of hotels you visited: ";

        cin >> iSize;



        for ( i = 0; i < iSize; i++ )

        {

                iCounter++;

                cout << "\nEnter total cost of hotel "

                                 << iCounter

                                 << ": $ ";

                cin >> dtemp;

                dhotel += dtemp;

        }

/* = = = = = = = = = = = = = = = = = = = = = = = = = = = =        */

cout << "\nTotal cost of hotel: $ "

                        << dhotel;



        return 0;

}

Output
--------
Enter number of hotels you visited: 2

Enter total cost of hotel 1: $ 1.00

Enter total cost of hotel 2: $ 1.00

Total cost of hotel: $ 0.00162506 :confused: What's going on here?

Everything looks fine to me, and when compiling and running the program on my Linux box I get the expected answer.
Something funky must be going on on your side...

I assume this isn't all the code; is it possible you reuse the variables elsewhere in the code and the numbers are getting overwritten?

What compiler are you using?

My only guess is you're using one that (oddly) doesn't support multiple variable initialization on the same line. If dHotel isn't getting initialized to 0, then you could see this problem.

Try putting double dHotel = 0.0; on its own line.

Additionally, is there a reason for using doubles, rather than floats? Save yourself a little bit of memory. :)

:thumbsup: It now works after Jinnkai's suggestion of each variable having it's own line. That's really weird because normally it works, maybe the compiler didn't like it this time, since I had so many variables on one line.

Variable initialization

Quote:

Originally Posted by zero2

A lot of compilers will sometimes (in debug mode) initialize variables to reasonable values.. what you did at the top:

double var1, var2, var3 = 0;

is initializing ONLY var3. Sometimes you can get lucky and var1 and var2 will be 0. the correct line would be:

double var1=0, var2 = 0, var3 = 0;