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16#include <cmath>

17#include <cstdint>

18#include <cstdlib>

19#include <sstream>

20#include <vector>

21

28

29

31

32struct DataModel {

33 const std::vector<std::vector<int>> locations{

34 {288, 149}, {288, 129}, {270, 133}, {256, 141}, {256, 157}, {246, 157},

35 {236, 169}, {228, 169}, {228, 161}, {220, 169}, {212, 169}, {204, 169},

36 {196, 169}, {188, 169}, {196, 161}, {188, 145}, {172, 145}, {164, 145},

37 {156, 145}, {148, 145}, {140, 145}, {148, 169}, {164, 169}, {172, 169},

38 {156, 169}, {140, 169}, {132, 169}, {124, 169}, {116, 161}, {104, 153},

39 {104, 161}, {104, 169}, {90, 165}, {80, 157}, {64, 157}, {64, 165},

40 {56, 169}, {56, 161}, {56, 153}, {56, 145}, {56, 137}, {56, 129},

41 {56, 121}, {40, 121}, {40, 129}, {40, 137}, {40, 145}, {40, 153},

42 {40, 161}, {40, 169}, {32, 169}, {32, 161}, {32, 153}, {32, 145},

43 {32, 137}, {32, 129}, {32, 121}, {32, 113}, {40, 113}, {56, 113},

44 {56, 105}, {48, 99}, {40, 99}, {32, 97}, {32, 89}, {24, 89},

45 {16, 97}, {16, 109}, {8, 109}, {8, 97}, {8, 89}, {8, 81},

46 {8, 73}, {8, 65}, {8, 57}, {16, 57}, {8, 49}, {8, 41},

47 {24, 45}, {32, 41}, {32, 49}, {32, 57}, {32, 65}, {32, 73},

48 {32, 81}, {40, 83}, {40, 73}, {40, 63}, {40, 51}, {44, 43},

49 {44, 35}, {44, 27}, {32, 25}, {24, 25}, {16, 25}, {16, 17},

50 {24, 17}, {32, 17}, {44, 11}, {56, 9}, {56, 17}, {56, 25},

51 {56, 33}, {56, 41}, {64, 41}, {72, 41}, {72, 49}, {56, 49},

52 {48, 51}, {56, 57}, {56, 65}, {48, 63}, {48, 73}, {56, 73},

53 {56, 81}, {48, 83}, {56, 89}, {56, 97}, {104, 97}, {104, 105},

54 {104, 113}, {104, 121}, {104, 129}, {104, 137}, {104, 145}, {116, 145},

55 {124, 145}, {132, 145}, {132, 137}, {140, 137}, {148, 137}, {156, 137},

56 {164, 137}, {172, 125}, {172, 117}, {172, 109}, {172, 101}, {172, 93},

57 {172, 85}, {180, 85}, {180, 77}, {180, 69}, {180, 61}, {180, 53},

58 {172, 53}, {172, 61}, {172, 69}, {172, 77}, {164, 81}, {148, 85},

59 {124, 85}, {124, 93}, {124, 109}, {124, 125}, {124, 117}, {124, 101},

60 {104, 89}, {104, 81}, {104, 73}, {104, 65}, {104, 49}, {104, 41},

61 {104, 33}, {104, 25}, {104, 17}, {92, 9}, {80, 9}, {72, 9},

62 {64, 21}, {72, 25}, {80, 25}, {80, 25}, {80, 41}, {88, 49},

63 {104, 57}, {124, 69}, {124, 77}, {132, 81}, {140, 65}, {132, 61},

64 {124, 61}, {124, 53}, {124, 45}, {124, 37}, {124, 29}, {132, 21},

65 {124, 21}, {120, 9}, {128, 9}, {136, 9}, {148, 9}, {162, 9},

66 {156, 25}, {172, 21}, {180, 21}, {180, 29}, {172, 29}, {172, 37},

67 {172, 45}, {180, 45}, {180, 37}, {188, 41}, {196, 49}, {204, 57},

68 {212, 65}, {220, 73}, {228, 69}, {228, 77}, {236, 77}, {236, 69},

69 {236, 61}, {228, 61}, {228, 53}, {236, 53}, {236, 45}, {228, 45},

70 {228, 37}, {236, 37}, {236, 29}, {228, 29}, {228, 21}, {236, 21},

71 {252, 21}, {260, 29}, {260, 37}, {260, 45}, {260, 53}, {260, 61},

72 {260, 69}, {260, 77}, {276, 77}, {276, 69}, {276, 61}, {276, 53},

73 {284, 53}, {284, 61}, {284, 69}, {284, 77}, {284, 85}, {284, 93},

74 {284, 101}, {288, 109}, {280, 109}, {276, 101}, {276, 93}, {276, 85},

75 {268, 97}, {260, 109}, {252, 101}, {260, 93}, {260, 85}, {236, 85},

76 {228, 85}, {228, 93}, {236, 93}, {236, 101}, {228, 101}, {228, 109},

77 {228, 117}, {228, 125}, {220, 125}, {212, 117}, {204, 109}, {196, 101},

78 {188, 93}, {180, 93}, {180, 101}, {180, 109}, {180, 117}, {180, 125},

79 {196, 145}, {204, 145}, {212, 145}, {220, 145}, {228, 145}, {236, 145},

80 {246, 141}, {252, 125}, {260, 129}, {280, 133},

81 };

82 const int num_vehicles = 1;

83 const RoutingIndexManager::NodeIndex depot{0};

84};

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89std::vector<std::vector<int64_t>> ComputeEuclideanDistanceMatrix(

90 const std::vector<std::vector<int>>& locations) {

91 std::vector<std::vector<int64_t>> distances =

92 std::vector<std::vector<int64_t>>(

93 locations.size(), std::vector<int64_t>(locations.size(), int64_t{0}));

94 for (int from_node = 0; from_node < locations.size(); from_node++) {

95 for (int to_node = 0; to_node < locations.size(); to_node++) {

96 if (from_node != to_node)

97 distances[from_node][to_node] = static_cast<int64_t>(

98 std::hypot((locations[to_node][0] - locations[from_node][0]),

99 (locations[to_node][1] - locations[from_node][1])));

100 }

101 }

102 return distances;

103}

104

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106

111void PrintSolution(const RoutingIndexManager& manager,

112 const RoutingModel& routing, const Assignment& solution) {

113 LOG(INFO) << "Objective: " << solution.ObjectiveValue();

114

115 int64_t index = routing.Start(0);

116 LOG(INFO) << "Route:";

117 int64_t distance{0};

118 std::stringstream route;

119 while (!routing.IsEnd(index)) {

120 route << manager.IndexToNode(index).value() << " -> ";

121 const int64_t previous_index = index;

122 index = solution.Value(routing.NextVar(index));

123 distance += routing.GetArcCostForVehicle(previous_index, index, int64_t{0});

124 }

125 LOG(INFO) << route.str() << manager.IndexToNode(index).value();

126 LOG(INFO) << "Route distance: " << distance << "mm";

127 LOG(INFO) << "";

128 LOG(INFO) << "Advanced usage:";

129 LOG(INFO) << "Problem solved in " << routing.solver()->wall_time() << "ms";

130}

131

132

133void Tsp() {

134

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136 DataModel data;

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141 RoutingIndexManager manager(data.locations.size(), data.num_vehicles,

142 data.depot);

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147 RoutingModel routing(manager);

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151 const auto distance_matrix = ComputeEuclideanDistanceMatrix(data.locations);

152 const int transit_callback_index = routing.RegisterTransitCallback(

153 [&distance_matrix, &manager](const int64_t from_index,

154 const int64_t to_index) -> int64_t {

155

156 const int from_node = manager.IndexToNode(from_index).value();

157 const int to_node = manager.IndexToNode(to_index).value();

158 return distance_matrix[from_node][to_node];

159 });

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164 routing.SetArcCostEvaluatorOfAllVehicles(transit_callback_index);

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168

170 searchParameters.set_first_solution_strategy(

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176 const Assignment* solution = routing.SolveWithParameters(searchParameters);

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180

181 PrintSolution(manager, routing, *solution);

182

183}

184}

185

186int main(int , char* []) {

187 operations_research::Tsp();

188 return EXIT_SUCCESS;

189}

190