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/*
* (C)2012 Michael Duane Rice All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer. 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. Neither the name of the copyright holders
* nor the names of contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
*/
/* $Id: isLeap.c 2325 2013-04-02 21:22:16Z swfltek $ */
/*
Return 1 if 'year' is a leap year, else 0.
*/
#include <stdlib.h>
unsigned char
is_leap_year(int year)
{
div_t d;
/* year must be divisible by 4 to be a leap year */
if (year & 3)
return 0;
/* If theres a remainder after division by 100, year is not divisible by 100 or 400 */
d = div(year, 100);
if (d.rem)
return 1;
/* If the quotient is divisible by 4, then year is divisible by 400 */
if ((d.quot & 3) == 0)
return 1;
return 0;
}
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