Пример #1
0
// 尝试某个着法,并返回着法状态,参阅"cchess.h"
bool TryMove(PositionStruct &pos, int &nStatus, int mv) {
  if (!pos.LegalMove(mv)) {
    nStatus = MOVE_ILLEGAL;
    return false;
  }
  if (!pos.MakeMove(mv)) {
    nStatus = MOVE_INCHECK;
    return false;
  }
  nStatus = 0;
  nStatus += (pos.LastMove().CptDrw > 0 ? MOVE_CAPTURE : 0);
  nStatus += (pos.LastMove().ChkChs > 0 ? MOVE_CHECK : 0);
  nStatus += (pos.IsMate() ? MOVE_MATE : 0);
  nStatus += pos.RepStatus(3) * MOVE_PERPETUAL; // 提示:参阅"position.cpp"中的"IsRep()"函数
  nStatus += (pos.IsDraw() ? MOVE_DRAW : 0);
  pos.UndoMakeMove();
  return true;
}
Пример #2
0
// 无害裁剪
static int HarmlessPruning(const PositionStruct &pos, int vlBeta) {
  int vl, vlRep;

  // 1. 杀棋步数裁剪;
  vl = pos.nDistance - MATE_VALUE;
  if (vl >= vlBeta) {
    return vl;
  }

  // 2. 和棋裁剪;
  if (pos.IsDraw()) {
    return 0; // 安全起见,这里不用"pos.DrawValue()";
  }

  // 3. 重复裁剪;
  vlRep = pos.RepStatus();
  if (vlRep > 0) {
    return pos.RepValue(vlRep);
  }

  return -MATE_VALUE;
}