text: /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
  /*
   *  Main authors:
   *     Christian Schulte <schulte@gecode.org>
   *
   *  Copyright:
   *     Christian Schulte, 2003
   *
   *  This file is part of Gecode, the generic constraint
   *  development environment:
   *     http://www.gecode.org
   *
   *  Permission is hereby granted, free of charge, to any person obtaining
   *  a copy of this software and associated documentation files (the
   *  "Software"), to deal in the Software without restriction, including
   *  without limitation the rights to use, copy, modify, merge, publish,
   *  distribute, sublicense, and/or sell copies of the Software, and to
   *  permit persons to whom the Software is furnished to do so, subject to
   *  the following conditions:
   *
   *  The above copyright notice and this permission notice shall be
   *  included in all copies or substantial portions of the Software.
   *
   *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
   *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   *
   */
  
  namespace Gecode { namespace Int { namespace Count {
  
    template<class VX, class VY, class VZ, bool shr, bool dom>
    forceinline
    EqView<VX,VY,VZ,shr,dom>::EqView(Home home,
                                     ViewArray<VX>& x, VY y, VZ z, int c)
      : ViewBase<VX,VY,VZ>(home,x,y,z,c) {}
  
    template<class VX, class VY, class VZ, bool shr, bool dom>
    ExecStatus
    EqView<VX,VY,VZ,shr,dom>::post(Home home,
                                   ViewArray<VX>& x, VY y, VZ z, int c) {
      GECODE_ME_CHECK(z.gq(home,-c));
      GECODE_ME_CHECK(z.lq(home,x.size()-c));
      if (isval(y) && z.assigned())
        return EqInt<VX,VY>::post(home,x,y,z.val()+c);
      if (sharing(x,y,z))
        (void) new (home) EqView<VX,VY,VZ,true,dom>(home,x,y,z,c);
      else
        (void) new (home) EqView<VX,VY,VZ,false,dom>(home,x,y,z,c);
      return ES_OK;
    }
  
    template<class VX, class VY, class VZ, bool shr, bool dom>
    forceinline
    EqView<VX,VY,VZ,shr,dom>::EqView(Space& home, EqView<VX,VY,VZ,shr,dom>& p)
      : ViewBase<VX,VY,VZ>(home,p) {}
  
    template<class VX, class VY, class VZ, bool shr, bool dom>
    Actor*
    EqView<VX,VY,VZ,shr,dom>::copy(Space& home) {
      return new (home) EqView<VX,VY,VZ,shr,dom>(home,*this);
    }
  
    template<class VX, class VY, class VZ, bool shr, bool dom>
    ExecStatus
    EqView<VX,VY,VZ,shr,dom>::propagate(Space& home, const ModEventDelta&) {
      count(home);
  
      GECODE_ME_CHECK(z.gq(home,atleast()));
      GECODE_ME_CHECK(z.lq(home,atmost()));
  
      if (z.assigned()) {
        if (z.val() == atleast()) {
          GECODE_ES_CHECK(post_false(home,x,y));
          return home.ES_SUBSUMED(*this);
        }
        if (z.val() == atmost()) {
          GECODE_ES_CHECK(post_true(home,x,y));
          return home.ES_SUBSUMED(*this);
        }
        if (!dom || isval(y)) {
          VY yc(y);
          GECODE_REWRITE(*this,(EqInt<VX,VY>
                                ::post(home(*this),x,yc,z.val()+c)));
        }
      }
  
  
      if (dom && !isval(y) && (z.min() > 0)) {
        /*
         * Only if the propagator is at fixpoint here, continue
         * when things are shared: the reason is that prune
         * requires that the views in x overlap with y!
         */
        if (shr && (VX::me(Propagator::modeventdelta()) != ME_INT_NONE))
          return ES_NOFIX;
  
        GECODE_ES_CHECK(prune(home,x,y));
  
        return ES_NOFIX;
      }
  
      return shr ? ES_NOFIX : ES_FIX;
    }
  
  }}}
  
  // STATISTICS: int-prop
  