void sjis2jis(int *p1, int *p2)
{
  unsigned char c1 = *p1;
  unsigned char c2 = *p2;
  int adjust = c2 < 159;
  int rowOffset = c1 < 160 ? 112 : 176;
  int cellOffset = adjust ? (c2 > 127 ? 32 : 31) : 126;

  *p1 = ((c1 - rowOffset) << 1) - adjust;
  *p2 -= cellOffset;
}