A textile plant has a number of automatic spinning machines that are assigned to operators who patrol the assigned area and repair any breaks that occur in the continuous filament fiber. The plant can be divided into 30 squares contained in a rectangle with a width of 5 and a length of 6. A patrol operator who is “based” in a square can patrol all machines in that square, as well as the eight adjacent squares. Formulate the problem of determining the minimum number of operators required to patrol the entire plant.

Provide the cover matrix. Solve the problem using a greedy heuristic algorithm and using the Excel® SOLVER tool.