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/*

FUNCTION

<<lldiv>>---divide two long long integers

INDEX

        lldiv

ANSI_SYNOPSIS

        #include <stdlib.h>

        lldiv_t lldiv(long long <[n]>, long long <[d]>);

TRAD_SYNOPSIS

        #include <stdlib.h>

        lldiv_t lldiv(<[n]>, <[d]>)

        long long <[n]>, <[d]>;

DESCRIPTION

Divide

@tex

$n/d$,

@end tex

@ifnottex

<[n]>/<[d]>,

@end ifnottex

returning quotient and remainder as two long long integers in a structure

<<lldiv_t>>.

RETURNS

The result is represented with the structure

. typedef struct

. {

.  long long quot;

.  long long rem;

. } lldiv_t;

where the <<quot>> field represents the quotient, and <<rem>> the

remainder.  For nonzero <[d]>, if `<<<[r]> = ldiv(<[n]>,<[d]>);>>' then

<[n]> equals `<<<[r]>.rem + <[d]>*<[r]>.quot>>'.

To divide <<long>> rather than <<long long>> values, use the similar

function <<ldiv>>.

PORTABILITY

<<lldiv>> is ISO 9899 (C99) compatable.

No supporting OS subroutines are required.

*/

/*-

 * Copyright (c) 2001 Mike Barcroft <mike@FreeBSD.org>

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#include <stdlib.h>

/*

 * The ANSI standard says that |r.quot| <= |n/d|, where

 * n/d is to be computed in infinite precision.  In other

 * words, we should always truncate the quotient towards

 * 0, never -infinity.

 *

 * Machine division and remainer may work either way when

 * one or both of n or d is negative.  If only one is

 * negative and r.quot has been truncated towards -inf,

 * r.rem will have the same sign as denom and the opposite

 * sign of num; if both are negative and r.quot has been

 * truncated towards -inf, r.rem will be positive (will

 * have the opposite sign of num).  These are considered

 * `wrong'.

 *

 * If both are num and denom are positive, r will always

 * be positive.

 *

 * This all boils down to:

 *      if num >= 0, but r.rem < 0, we got the wrong answer.

 * In that case, to get the right answer, add 1 to r.quot and

 * subtract denom from r.rem.

 */

lldiv_t

_DEFUN (lldiv, (number, denom),

       long long numer _AND long long denom)

{

        lldiv_t retval;

        retval.quot = numer / denom;

        retval.rem = numer % denom;

        if (numer >= 0 && retval.rem < 0) {

                retval.quot++;

                retval.rem -= denom;

        }

        return (retval);

}