Originally posted by: TRAN Van Ut

Hello,

For coding this model,  I write as below . 

forall(k in 1..n)
    sum(l in 1..k, j in 1..n)(p[j]*x[j][l])- sum(j in 1..n)(d[j]*x[j][k])
<
=0;

I think maybe there are the problems in my coding. Please help me ro repair.

All the best,

Thank you in advance!