各位高人，现有一求解问题
满足 MAx ∑(4-i+1)(au_i+(1-a)v_i) 1<=i<=4 , 1>=a>=0 ,a为任意输入的常数

其中 u_{i ,}v_{i 为整数}
u₁<=13
u₁+u₂<=45
u₁+u₂+u₃<=69
u₁+u₂+u₃+u₄<=79
v₁<=35
v₁+v₂<=37
v1+v2+v3<=65
v1+v2+v3+v4<=85
0<=u_i<=25 i=1,2,3,4
0<=v_i<=30 i=1,2,3,4
v_i+1.5u_i<=52.5 i=1,2,3,4
v_i+2.25u_i<=68.25 i=1,2,3,4

求解u_i, v_i