MODEL.setObjective(-3*x-2*y-z,GRB.MINIMIZE) MODEL.addConstr(x+y+z<=7,'c0') MODEL.addConstr(4*x+2*y+z==12,'c1') MODEL.addConstr(x>=0,'c2') MODEL.addConstr(y>=0,'c3') MODEL.addConstr(z==0 or z==1 ,'c4')#这里的 z等于0或1怎么表示