Division, Remainders and only Real Numbers Allowed

Question

Trying to figure out this pseudo code. The following is assumed.... I can only use unsigned and signed integers (or long). Division returns a real number with no remainder. MOD returns a real number. Fractions and decimals are not handled.

INT I = 41828;
INT C = 15;
INT D = 0;

D = (I / 65535) * C;

How would you handle a fraction (or decimal value) in this situation? Is there a way to use negative value to represent the remainder?

In this example I/65535 should be 0.638, however, with the limitations, I get 0 with a MOD of 638. How can I then multiply by C to get the correct answer?

Hope that makes sense.

MOD here would actually return 23707, not 638. (I hope I'm right on that :) )

Answer 1

If you were to switch your order of operations on that last line, you would get the integer answer you're looking for (9, if my calculations are correct)

D = (I * C) / 65535
/* D == 9 */

Is that the answer you're looking for?

Answer 2

Well, one way to handle decimals is this replacement division function. There are numerous obvious downsides to this technique.

ALT DIV (dividend, divisor) returns (decimal, point)
for point = 0 to 99
  if dividend mod divisor = 0 return dividend / divisor, point
  dividend = divident * 10
return dividend / divisor, 100