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Help with C++

  1. May 28, 2010 #1
    I am pretty ignorant of this language. I am working from a '...for dummies' book to teach myself and after the first few pages I have already stumbled upon a problem. I have attached a code, pretty simple one, which I'm trying to run but there are some errors and I don't know how to resolve them. I am using eclipse and when I debug I get a message which says 'program file does not exist.' If someone can help me with this I would appreciate it.

    Attached Files:

    • code.txt
      File size:
      909 bytes
  2. jcsd
  3. May 29, 2010 #2


    Staff: Mentor

    What errors are you getting? If there are compiler errors (as opposed to warnings), the compiler will not generate a program file, so you can't debug.

    The first thing I notice is a malformed comment ( / ) in the first line.

    Something much less serious, but not incorrect, is the conversion formula, which is more complicated than it needs to be.
    Fahrenheit = Celsius *(212 - 32)/100 + 32

    This is exactly the same as Fahrenheit = Celsius *9/5 + 32, since (212 - 32)/100 = 180/100 = 9/5.
    Code (Text):

    // Program to convert temperature from Celsius degree units into Fahrenheit degree
    // units into Fahrenheit degree units:
    // Fahrenheit = Celsius *(212 - 32)/100 + 32
    #include <cstdio>
    #include <cstdlib>
    #include <iostream>
    using namespace std;

    int main(int nNumberofArgs, char* pszArgs[])
    // enter the temperature in Celsius
    int celsius;
    cout << "Enter the temperature in Celsius:";
    cin >> celsius;
    // calculate conversion factor for Celsius
    // to Fahrenheit values
    int factor;
    factor = 212 - 32;

    // use conversion factor to convert Celsius
    // into Fahrenheit values
    int fahrenheit;
    fahrenheit = factor * celsius/100 + 32;

    // output the results (followed by a NewLine)
    cout << "Fahrenheit value is";
    cout << fahrenheit << endl;

    // wait until user is ready before terminating program
    // to allow the user to see the program results
    return 0;

  4. May 29, 2010 #3


    User Avatar
    Science Advisor
    Homework Helper

    fahrenheit = factor * celsius/100 + 32;

    Doesn't do what you think it does.
    For anything below boiling point it will return 32.
  5. May 29, 2010 #4


    Staff: Mentor

    I agree with the "doesn't do what you think it does" part, but if celsius is a multiple of 10, the formula will give the right result. If celsius is not a multiple of 10, the results will be surprising to someone who doesn't understand integer division in C and C++.

    The * and / operators are at the same precedence level, and are evaluated left to right.
  6. May 29, 2010 #5
    I corrected it, but its still doing the same thing.
  7. May 29, 2010 #6
    You're running it in eclipse? With what compiler? My guess with that error message is that you don't have the right plugins installed in the IDE. I've never worked with C++ in eclipse, but I think there is a development kit called CDT that you can use. Did you try a different IDE? I got this code to work in visual studio, so I don't know what the problem is.

    The only thing is you have to add the standard header file
    #include "stdafx.h"

    Let us know if you're still getting errors and what they say. See if you can get it to compile with something besides eclipse.
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