Thread: Temperature conversion...

Hi, I'm new at C programming, and I'm following the HowStuffWorks.com C programming tutorial/guide until I get some books- it has nice examples and lets you experiment. Anyways, I'm working on a temperature conversion program- a basic loop project. I'm trying to convert Fahrenheit to Celcius with user-inputted starting temp, ending temp, and increment value. Problem is, IT KEEPS REPEATING. I've spent an hour trying to figure out why, but i can't find the cause of it all. So here's the code. Thanks

Code:

#include <stdio.h>

int main()
{

float a, b, c, d;
 printf("Enter a value for the starting temperature in Fahrenheit:");
   scanf("%f", b);
   printf("Enter a value for the ending temperature in Fahrenheit:");
   scanf("%f", c);
   printf("Enter a value for the temperature increment value in Fahrenheit:");
   scanf("%f", d);
   a = b;
   printf("This is a Fahrenheit to Celcius Conversion Table!");
    while (a <= c)
    {
       if ((a > 98.6) && (a < (a + d)))
        {

           printf("%f degrees F = %f degrees C\n",
               98.6, (98.6 - 32.0) * 5.0 / 9.0);

        }

        printf("%f degrees F = %f degrees C\n",
            a, (a - 32.0) * 5.0 / 9.0);
        a = (a + d);

    }

    return 0;

}