a searching unit to search {TAIL ~ the route information} of {HEAD ~ the respective links} connected via the respective node corresponding to the starting position; and 
a searching unit to search { TAIL ~ the route information } of { HEAD ~ the respective links } connected via the respective node corresponding to the starting position ; and
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH