Algorithm 1

Suboptimal Solution for DC Problems

1) Initialize $x^{\left(0\right)}$ , set iteration number $k=0$ .

2) do { define convex approximation of $q^{\left(k\right)}\left(x\right)$ as

3) ${\widehat{q}}^{\left(k\right)}\left(x\right)=f\left(x\right)-g\left(x^{\left(k\right)}\right)-\nabla g^{\text{T}}\left(x^{\left(k\right)}\right)\left(x-x^{\left(k\right)}\right)$ (15)

4) solve the convex problem

5) $x^{\left(k+1\right)}=\underset{x\in \chi }{\arg \min }{\widehat{q}}^{\left(k\right)}\left(x\right)$ (16)

6) $k++$

7) } while ( $\left|q\left(x^{\left(k+1\right)}\right)-q\left(x^{\left(k\right)}\right)\right|\ge \epsilon$ );

8) end