#Python Code include: #Problem Narration #Define Gurobi model using python #Set and their explanation #Parameter / data and their description #decision variabel and their explanation #Contsraint and their explanation #run optimization and their explanation #Print the result and explanation

15.4 Gritting roads In the case of ice, all the streets of a village need to be gritted. A schematic map of the streets is given in Figure 15.8. The nodes correspond to street intersections, the arcs to the streets that need to be gritted. The arcs are labeled with the length of the street in meters. 150 140 100 2 3 130 100 230 165 165 170 200 190 160 180 144 122 109 5 6 7 8 144 128 4 194 174 174 185 185 190 218 233 141 10 11 12 148 135 110 Figure 15.8: Graph of the village streets Local authorities and public services 237 Applications of optimization with Xpress-MP The highway maintenance depot with the gritting truck is located at intersection number 1. The truck has a sufficiently large capacity to grit all the streets during a single tour. Due to the one-way streets, it may be forced to pass several times through the same street that has already been gritted. Determine a tour for the gritting truck of minimum total length that passes through all streets. For bidirectional streets, both directions need to be gritted separately. 15.4 Gritting roads In the case of ice, all the streets of a village need to be gritted. A schematic map of the streets is given in Figure 15.8. The nodes correspond to street intersections, the arcs to the streets that need to be gritted. The arcs are labeled with the length of the street in meters. 150 140 100 2 3 130 100 230 165 165 170 200 190 160 180 144 122 109 5 6 7 8 144 128 4 194 174 174 185 185 190 218 233 141 10 11 12 148 135 110 Figure 15.8: Graph of the village streets Local authorities and public services 237 Applications of optimization with Xpress-MP The highway maintenance depot with the gritting truck is located at intersection number 1. The truck has a sufficiently large capacity to grit all the streets during a single tour. Due to the one-way streets, it may be forced to pass several times through the same street that has already been gritted. Determine a tour for the gritting truck of minimum total length that passes through all streets. For bidirectional streets, both directions need to be gritted separately