IDX
#define IDX(c) ((u_char)(c) / LONG_BIT)
#define IDX(c) ((u_char)(c) / LONG_BIT)
# define IDX(h) ((( h >> (3*8 - HLOG)) - h ) & (HSIZE - 1))
# define IDX(h) ((( h >> (3*8 - HLOG)) - h*5) & (HSIZE - 1))
# define IDX(h) ((((h ^ (h << 5)) >> (3*8 - HLOG)) - h*5) & (HSIZE - 1))
# define IDX(h) ((h) & (HSIZE - 1))
#define IDX(c) ((u_char)(c) / LONG_BIT)
#define IDX(c) ((u_char)(c) / LONG_BIT)