extern struct datum    *rootdat, *curdat, *holddat;
extern struct simp     *rootsimp, *cursimp, *holdsimp, *lastsimp, *prevsimp;
extern struct temp     *roottemp, *curtemp, *lasttemp, *prevtemp;
extern struct neig     *rootneig, *curneig, *lastneig;
extern struct asinfo   curas;
