{TAIL ~ A distribution graph} including {HEAD ~ the nodes} involved in the distribution spanned out by logical links assigned cost values is constructed 
{ TAIL ~ A distribution graph } including { HEAD ~ the nodes } involved in the distribution spanned out by logical links assigned cost values is constructed
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH