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/**************************************************************************/
/* */
/* The Why platform for program certification */
/* Copyright (C) 2002-2008 */
/* Romain BARDOU */
/* Jean-Franois COUCHOT */
/* Mehdi DOGGUY */
/* Jean-Christophe FILLITRE */
/* Thierry HUBERT */
/* Claude MARCH */
/* Yannick MOY */
/* Christine PAULIN */
/* Yann RGIS-GIANAS */
/* Nicolas ROUSSET */
/* Xavier URBAIN */
/* */
/* This software is free software; you can redistribute it and/or */
/* modify it under the terms of the GNU General Public */
/* License version 2, as published by the Free Software Foundation. */
/* */
/* This software is distributed in the hope that it will be useful, */
/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. */
/* */
/* See the GNU General Public License version 2 for more details */
/* (enclosed in the file GPL). */
/* */
/**************************************************************************/
/*@ axiom times_0: \forall integer x; 0 * x == 0 */
/*@ axiom times_S: \forall integer d, integer x; (d+1) * x == d * x + x */
/*@ requires
@ x >= 0 && y > 0
@ ensures
@ 0 <= \result < y &&
@ \exists integer d; x == d * y + \result
@*/
int math_mod(int x, int y) {
/*@ invariant 0 <= x && \exists integer d; \old(x) == d * y + x
@ variant x
@*/
while (x >= y) x = x - y;
return x;
}
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