1  typedef struct
       2  {
       3    short v, h;
       4  } S;
       5  
       6  S a;
       7  
       8  f (S pnt)
       9  {
      10    S mpnt, mtp;
      11  
      12    (&pnt)->v -= 1;
      13    mpnt = pnt;
      14    mtp = a;
      15    if (mtp.v != mpnt.v)
      16      {
      17        S tpnt;
      18  
      19        tpnt = mtp;
      20        mtp = mpnt;
      21        mpnt = tpnt;
      22      }
      23  }