 such that any solution S(i, j) has neighbors S(i \+ 0, j \+ 0), S(i \+ 0, j − 0), S(i − 0, j \+ 0), and S(i − 0, j − 0), whenever they exist. Figure 0.0 displays the search space graph defined by this neighborhood.  Fig. 0.0  Search space graph with 00 feasible solutions and neighborhood N 0.  