minimize 0.5*sum(i in t效)((pti-pli)+sum(J in number)pevchi*ci+sum(j in number)-pevdisi*ci);但以{35:ct1:forall(i in t效) {if(pli<7000000) ci==2.5;ct2:if(7000000<=pli<=10000000) ci==3.5;ct5 3:if(pli>10000000) ci==5;} ct5 4:forall(i in t效,j in number) {ct5:if(pti-pli