graphopt : ENEXT LEFT_PAREN STRING {strcpy(GraphNextName,strval);} RIGHT_PAREN
         | EVERTEX LEFT_PAREN STRING {strcpy(GraphVertexName,strval);} RIGHT_PAREN
         | EHEAD LEFT_PAREN STRING {strcpy(GraphHeadName,strval);} RIGHT_PAREN
         | ADJLIST LEFT_PAREN STRING {strcpy(AdjListName,strval);} RIGHT_PAREN
         | VCOUNT LEFT_PAREN STRING {strcpy(VCountName,strval);} RIGHT_PAREN
         | ECOUNT LEFT_PAREN STRING {strcpy(ECountName,strval);} RIGHT_PAREN
         | EDGEPROB LEFT_PAREN STRING {EdgeProbYes = strtol(strval,NULL,0);} RIGHT_PAREN
         | EDGEPROB LEFT_PAREN STRING {EdgeProbYes = strtol(strval,NULL,0);} COMMA STRING {EdgeProbNo = strtol(strval,NULL,0);} RIGHT_PAREN
         | EDGECOUNT LEFT_PAREN STRING {strcpy(EdgeCountSel,strval);} RIGHT_PAREN
         | DIRECTED {DirectedGraph = 1;}
