A greedy randomized adaptive search procedure (GRASP) is a metaheuristic for combinatorial optimization. GRASP heuristics are multistart procedures which apply local search to a set of starting solutions generated with a randomized greedy algorithm or semi-greedy method. The best local optimum found over the iterations is returned as the heuristic solution. Path-relinking is a search intensification procedure that explores paths in the neighborhood solution space connecting two good-quality solutions. A local search procedure is applied to the best solution found in the path and the local optimum found is returned as the solution of path-relinking. The hybridization of path-relinking and GRASP adds memory mechanisms to GRASP. This paper describes basic concepts of GRASP, path-relinking, and the hybridization of GRASP with path-relinking.
AT&T Labs Research Technical Report, Florham Park, NJ 07733 USA, October 2011.