“…Difference-of-convex (DC) programming has been an active area of research in nonconvex and nonsmooth optimization [19,20,49,44,27,1,42]. They arise in extensive applications such as sparsity learning [55,28], clustering [23], molecular conformation [25], trust region subproblem [45,7], portfolio optimization [48,47,38], control theory [36], natural language processing [40], image denoising [56], mixed-integer optimization [22,35,31,39] and eigenvalue complementarity problem [24,37,34,33], to name a few; see [27] and the references therein for a comprehensive introduction about DC programming and its applications.…”