Apparently, x86 (and probably a lot of other instruction sets) put both the quotient and the remainder of a divide operation in separate registers.
Now, we can proba
Python does.
>>> divmod(9, 4)
(2, 1)
Which is odd, becuase Python is such a high level language.
So does Ruby:
11.divmod(3) #=> [3, 2]
* EDIT *
It should be noted that the purpose of these operators is probably not to do the work as efficiently as possible, it is more likely the functions exist for correctness/portability reasons.
For those interested, I believe this is the code of the Python implementation for integer divmod:
static enum divmod_result
i_divmod(register long x, register long y,
long *p_xdivy, long *p_xmody)
{
long xdivy, xmody;
if (y == 0) {
PyErr_SetString(PyExc_ZeroDivisionError,
"integer division or modulo by zero");
return DIVMOD_ERROR;
}
/* (-sys.maxint-1)/-1 is the only overflow case. */
if (y == -1 && UNARY_NEG_WOULD_OVERFLOW(x))
return DIVMOD_OVERFLOW;
xdivy = x / y;
/* xdiv*y can overflow on platforms where x/y gives floor(x/y)
* for x and y with differing signs. (This is unusual
* behaviour, and C99 prohibits it, but it's allowed by C89;
* for an example of overflow, take x = LONG_MIN, y = 5 or x =
* LONG_MAX, y = -5.) However, x - xdivy*y is always
* representable as a long, since it lies strictly between
* -abs(y) and abs(y). We add casts to avoid intermediate
* overflow.
*/
xmody = (long)(x - (unsigned long)xdivy * y);
/* If the signs of x and y differ, and the remainder is non-0,
* C89 doesn't define whether xdivy is now the floor or the
* ceiling of the infinitely precise quotient. We want the floor,
* and we have it iff the remainder's sign matches y's.
*/
if (xmody && ((y ^ xmody) < 0) /* i.e. and signs differ */) {
xmody += y;
--xdivy;
assert(xmody && ((y ^ xmody) >= 0));
}
*p_xdivy = xdivy;
*p_xmody = xmody;
return DIVMOD_OK;
}