med3
pl = med3(pl, pl + s, pl + 2 * s, cmp);
pm = med3(pm - s, pm, pm + s, cmp);
pn = med3(pn - 2 * s, pn - s, pn, cmp);
pm = med3(pl, pm, pn, cmp);
static __inline char *med3(char *, char *, char *, int (*)(const void *, const void *));
pl = med3(pl, pl + d, pl + 2 * d, cmp);
pm = med3(pm - d, pm, pm + d, cmp);
pn = med3(pn - 2 * d, pn - d, pn, cmp);
pm = med3(pl, pm, pn, cmp);
static __inline char *med3(char *, char *, char *, int (*)(const void *, const void *));
pl = med3(pl, pl + d, pl + 2 * d, cmp, p);
pm = med3(pm - d, pm, pm + d, cmp, p);
pn = med3(pn - 2 * d, pn - d, pn, cmp, p);
pm = med3(pl, pm, pn, cmp, p);
static __inline char *med3(char *, char *, char *,