“…It is a very general approach, in the sense that if v − g 2 /2 is replaced with an arbitrary convex (C 1 , otherwise some (simple) adaption is required) potential i i (v i ), then (17) can be tackled in the same way with obvious modification (and this is, in general, optimal). However, for some "simple" potentials and in particular the one in (17), the method described in Eisner and Severance (1976), Gallo et al (1989), Hochbaum (2001) computes the exact solution (of course, in practice, up to machine precision) and is therefore optimal. We will return to this later on, when discussing the practical implementation, see Sect.…”