LABMAX
char _ldis[LABMAX][LABLEN+1]; /* labels suitable to display */
char _lval[LABMAX][LABLEN+1]; /* labels' true values */
short _labx[LABMAX]; /* where to display labels */
bool _lch[LABMAX]; /* change status */
if ((j += gp[i]) > LABMAX)
int grpx[LABMAX];
static int _ngroups, _groups[LABMAX];