addedge
addedge(od, reqq.elements[i], reqq.elements[j], pre == TYPE_PREREQ ? TYPE_PREREQ_P : TYPE_REQ_P);
addedge(od, p, p2, pre);
addedge(od, p, p2, pre == TYPE_PREREQ ? TYPE_PREREQ_P : TYPE_REQ_P);
addedge(od, p2, p, pre == TYPE_PREREQ ? TYPE_PREREQ_P : TYPE_REQ_P);
addedge(od, p2, p, TYPE_CON);
addedge(od, p, p2, TYPE_CON);
addedge(od, p2, p, TYPE_CON);
ret |= addedge(od, ti.elements[i], to, type);
ret |= addedge(od, from, ti.elements[i], type);