The following problem has only two integer variables; however, they appear in the index of the parameters. Appreciate it if anyone has any efficient idea to transform it into a canonical integer programming model.
$$ \begin{alignat*}{2} &&\max \quad & (d_y - d_x)^2 \\ &&\text{s.t.} \quad & d_y - d_x \geq \alpha \\ && & x,y \in \mathbb{Z}_+ \\ \end{alignat*} $$