Newbie Program That Started Off Easy - Simple Math w/ Interactive Menu

From: Mike (azrent_at_gmail.com)
Date: 10/31/04

  • Next message: john: "Re: C... Why not c++?" 
    Date: 30 Oct 2004 18:52:51 -0700

    Hello,

    This program uses C. It is meant to convert whatever the current
    exchange rate is to dollars. It compiles, builds, and executes
    correctly except for a few bugs. When building I get an error that
    states;

    Linker Error (Severity 4)
    Module "a" in file "c:\program files\miracle c\yendollarext.obj"
    references unresolved external "_rewind"
    at offset 0303H in segment "_text".

    I am not sure how to resolve this error.

    Also, I attempted to have the program create an error whenever someone
    either "chooses" a number higher than 1 "else if(choice > '1')" or
    attempts to use an alpha character

    "if (isalpha(yen))

    {

    printf("\n Sorry, that was not a valid option.\n\n");"

    break;

    in which the program shuts down without displaying the error message.
    Any ideas? Here is the code, all help is appreciated.

    #include <stdio.h>
    #define DRAINO rewind(stdin);fflush(stdout);
    #define STOP rewind(stdin); getchar();

    int main( void )
    {
      double yen = 0.0;
      double dollars = 0.0;
      double yentoDollar = 0.0;

      int choice=0;
     

    printf("\nYen to Dollar Currency Conversion\n\n");

    printf("Enter 1 to begin Conversionn\n");

    printf("Enter 0 to Quit the Program\n\n");

    printf("Please select your option:\n\n");

    scanf("%d", &choice);

    if (choice == 1)

    {

      printf("\nYou want to convert Yen into US dollars.\n\n");
      printf("Please enter the current exchange rate between Dollars and
    Yen.\n\n");
      scanf( "%lf", &yentoDollar );
      
     
      if (isalpha(yentoDollar))

    {

    printf("Sorry, that was not a valid option.");
    getchar ();
    break;

    }

      printf("\nHow many Yen do you have?\n\n");
      scanf( "%lf", &yen );
      if (isalpha(yen))

    {

    printf("\n Sorry, that was not a valid option.\n\n");

    break;

    }
      dollars = yen * yentoDollar;
      printf( "\nThe conversion to US dollars of %.2f yen is %.2f
    dollars\n", yen, dollars );
      
      
    rewind(stdin);

    getchar();

     }

    else if (choice == 0)

    {
    printf("Program will terminate after you click Enter.\n");
    printf("\nHave a nice day!");
    getchar ();
    return 0;
      
    }

    else if(choice > '1')

    {

    printf("\nProgram will terminate after you click Enter.\n");
    printf("\nHave a nice day!");
    getchar ();
    return 0;

    }
     
    }

    Thanks in advance!

    Mike

  • Next message: john: "Re: C... Why not c++?"

    Relevant Pages

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      ... exchange rate between U.S. dollars and Japanese yen, ... #define STOP rewind; getchar(); ... dollars = yen * yentoDollar; ... printf("Program will terminate after you click Enter.\n"); ...
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    • Re: Newbie Program That Started Off Easy - Simple Math w/ Interactive Menu
      ... > newsgroup dealing with your compiler. ... dollars = yen * yentoDollar; ... printf("Program will terminate after you Press Enter.\n"); ...
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