  We calculate ground-state properties of a many-quark system in the
string-flip model using variational Monte Carlo methods. The many-body
potential energy of the system is determined by finding the optimal grouping of
quarks into hadrons. This (optimal) assignment problem is solved by using the
stochastic optimization technique of simulated annealing. Results are presented
for the energy and length-scale for confinement as a function of density. These
results show how quarks clustering decreases with density and characterize the
nuclear- to quark-matter transition. We compare our results to a previously
published work with a similar model which uses, instead, a pairing approach to
the optimization problem.
