Thread: I need help.

I am currently writing a program in C for a currnecy converter.
I have hit a wall right at the start:


float ster;
float char;
ster=0;
eur=0;
ster=eur*0.7:

printf("Enter amount in Euro\n");
scanf("%f", &eur);

printf("The equivalent in Sterling is %f", &ster);


This much doesn't work!
The equivalent just prints off as 0.0000
Hmm?

You have intialized eur=0;
do initialize
float eur=0.0;

Ah yes. Thanks.
Another quick question, is it possible to nest switches or will they overlap and cause all sorts of infinite loops etc.?

This seems to interfere with itself, maybe I have made an obvious mistake:

Code:

#include <stdio.h>

main()
{
char ch;
int num;
float eur=0.0;
float ster=0.0;




printf("Choose a country for currency conversion\n");
printf ("A.Britain\nB.Denmark\nC.Japan\nD.USA\nE.Exit\n"); 
scanf("%c", &ch);
switch (ch)   
{
	case 'a' :
 		printf("Do you wish to convert:\n");
 		printf("1.From Euro to Sterling\n2.From Sterling to Euro\n");
 		scanf("%d", &num);
      switch (num)
      {
      	case '1' :
         	printf("Enter amount in Euro\n");
  				scanf("%f", &eur);
  				ster=eur*0.70;
  				printf("The equivalent in Sterling is %4.2f", ster);
            break;
         case '2'  :
			   printf("Enter amount in Sterling\n");
            break;
         default :
         	printf("invalid entry");
      }

   case 'b' :
   	printf("YO");
      break;

   default :
   	printf("invalid entry");

Thanks very much.
How would I go about looping back to the original menu after each conversion? Do I use the do-while statement?

I put the break in on case 'A' but now the program freezes immediatley after case A is entered.

This is it, but putting the break above case 'b' doesn't work either.

Code:

#include <stdio.h>

main()
{
char ch;
char ch1;
float eur=0.0;
float ster=0.0;




printf("Choose a country for currency conversion\n");
printf ("A.Britain\nB.Denmark\nC.Japan\nD.USA\nE.Exit\n");  
scanf("%c", &ch);
switch (ch)
{
	case 'a' :
   case 'A' :
 		printf("Do you wish to convert:\n");
 		printf("1.From Euro to Sterling\n2.From Sterling to Euro\n");
 		scanf("%c", &ch1);
      break;

      switch (ch1)
      {
      	case '1' :
      		printf("Enter amount in Euro\n");
       		scanf("%f", &eur);
       		ster=eur*0.70;
       		printf("The equivalent in Sterling is %4.2f", ster);
         	break;

         case '2' :
       		printf("Enter amount in Sterling\n");
            scanf("%f", &ster);
            eur=ster*1.42;
            printf("The equivalent in Euro is %4.2f", eur);
         	break;

         default:
      		printf("invalid entry");
         	break;
      }


   case 'b' :
   case 'B' :
   	printf("...");
      break;

   default :
   	printf("invalid entry");
}
}

I see a big struggle coming up over the way scanf() handles the %c conversion...

If you type in 'A' followed by return into this code, you get what is in the comments

Code:

scanf("%c", &ch);  // Stores the character 'A' in ch
switch (ch)
{
   case 'a' :
   case 'A' :
        printf("Do you wish to convert:\n");
        printf("1.From Euro to Sterling\n2.From Sterling to Euro\n");
        scanf("%c", &ch1);  // Stores a newline in ch1
        switch (ch1)

http://faq.cprogramming.com/cgi-bin/...&id=1043284385

Code:

char buff[BUFSIZ];
fgets( buff, BUFSIZ, stdin );
switch (buff[0])
{
   case 'a' :
   case 'A' :
        printf("Do you wish to convert:\n");
        printf("1.From Euro to Sterling\n2.From Sterling to Euro\n");
        fgets( buff, BUFSIZ, stdin );
        switch (buff[0])

Tip for posting code - make sure your editor is set to only use spaces for indentation. If you mix spaces and tabs, your editor may cope and produce nice code, but it will look a mess when posted on a message board, even when it is within code tags.

You also might want to consider using some functions to stop your nested switch statements getting out of hand

Code:

char buff[BUFSIZ];
fgets( buff, BUFSIZ, stdin );
switch (buff[0])
{
   case 'a' :
   case 'A' :
        do_sterling();
        break;