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ea8c728 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 | #pragma once
// standart imports
#include <string>
#include <vector>
#include <limits>
#include <iostream>
// global variables declaration
constexpr int null = -1;
constexpr double e = 2.718281;
constexpr double inf_double = std::numeric_limits<double>::infinity();
constexpr int inf_int32 = std::numeric_limits<int>::max();
constexpr long long inf_int64 = std::numeric_limits<long long>::max();
enum class CandidatesSource { KNN, HeatMap };
enum class DistanceType { Int32, Int64, Double };
struct Config {
int cities_number;
std::string input_path;
std::string output_path;
bool use_heat_map_as_initial_weights;
CandidatesSource candidates_source;
int candidates_number;
int max_k_opt_depth;
bool random_k_opt_depth_after_first_iteration;
double min_potential_to_consider;
double exploration_coefficient;
double weight_delta_coefficient;
bool use_sensitivity_decrease;
double sensitivity_temperature;
int max_k_opt_simulations_without_improve_to_stop;
int restarts_number;
DistanceType distance_type;
double magnify_rate;
Config(const json& config) {
cities_number = config["cities_number"];
input_path = config["input_path"];
output_path = config["output_path"];
use_heat_map_as_initial_weights = config["use_heat_map_as_initial_weights"];
if (config["candidates_source"].get<std::string>() == "knn") {
candidates_source = CandidatesSource::KNN;
} else if (config["candidates_source"].get<std::string>() == "heat_map") {
candidates_source = CandidatesSource::HeatMap;
} else {
throw std::invalid_argument("Unknown candidates source: '" + config["candidates_source"].get<std::string>() + "'.");
}
candidates_number = config["candidates_number"];
max_k_opt_depth = config["max_k_opt_depth"];
random_k_opt_depth_after_first_iteration = config["random_k_opt_depth_after_first_iteration"];
min_potential_to_consider = config["min_potential_to_consider"];
exploration_coefficient = config["exploration_coefficient"];
weight_delta_coefficient = config["weight_delta_coefficient"];
use_sensitivity_decrease = config["use_sensitivity_decrease"];
sensitivity_temperature = config["sensitivity_temperature"];
max_k_opt_simulations_without_improve_to_stop = config["max_k_opt_simulations_without_improve_to_stop"];
restarts_number = config["restarts_number"];
if (config["distance_type"].get<std::string>() == "int32") {
distance_type = DistanceType::Int32;
} else if (config["distance_type"].get<std::string>() == "int64") {
distance_type = DistanceType::Int64;
} else if (config["distance_type"].get<std::string>() == "double") {
distance_type = DistanceType::Double;
} else {
throw std::invalid_argument("Unknown distance type: '" + config["distance_type"].get<std::string>() + "'.");
}
magnify_rate = config["magnify_rate"];
// warnings
if (distance_type == DistanceType::Double) {
if (cities_number > 1'000'000) {
std::cout << "Warning: `cities_number` is greater than 1'000'000. Try to use with `distance_type` = 'int64' to avoid precision errors.\n";
}
} else {
if (magnify_rate < 10'000.0) {
std::cout << "Warning: `magnify_rate` is better to take more than 10'000 when using with `distance_type` = 'int32' or 'int64'.\n";
}
if (distance_type == DistanceType::Int32 && static_cast<long long>(cities_number) * magnify_rate > 1'000'000'000) {
std::cout << "Warning: distance might be out of bounds for a 32 bit integer. Consider switching to doubles for distance calculation or using 64 bit integers.\n";
}
if (distance_type == DistanceType::Int64 && magnify_rate > 1'000'000'000) {
std::cout << "Warning: distance might be out of bounds for a 64 bit integer. Consider switching to doubles for distance calculation.\n";
}
}
}
};
struct City {
int prev;
int next;
};
struct Context {
// coordinates
double* coordinates_double_x = nullptr;
double* coordinates_double_y = nullptr;
int* coordinates_int32_x = nullptr;
int* coordinates_int32_y = nullptr;
long long* coordinates_int64_x = nullptr;
long long* coordinates_int64_y = nullptr;
// distances
double* distance_double = nullptr;
int* distance_int32 = nullptr;
long long* distance_int64 = nullptr;
// weights
double* heat_map = nullptr;
double* weight = nullptr;
double* total_weight = nullptr;
double* potential = nullptr;
// candidates
int* candidates = nullptr;
// local k opt search
int* pairs = nullptr;
int* saved_pairs = nullptr;
int saved_depth = 0;
double current_best_delta_double = -inf_double;
int current_best_delta_int32 = -inf_int32;
long long current_best_delta_int64 = -inf_int64;
long long* chosen_times = nullptr;
long long total_simulations = 0;
// path
City* path = nullptr;
double path_distance_double = inf_double;
int path_distance_int32 = inf_int32;
long long path_distance_int64 = inf_int64;
City* best_path = nullptr;
double best_path_distance_double = inf_double;
int best_path_distance_int32 = inf_int32;
long long best_path_distance_int64 = inf_int64;
int* solution;
std::vector<bool> is_city_selected;
// other utils/tmp variables
std::vector<int> buffer;
Context(const Config& config) : buffer(config.cities_number, 0), is_city_selected(config.cities_number, false) {
coordinates_double_x = new double[config.cities_number];
coordinates_double_y = new double[config.cities_number];
if (config.distance_type == DistanceType::Int32) {
coordinates_int32_x = new int[config.cities_number];
coordinates_int32_y = new int[config.cities_number];
}
if (config.distance_type == DistanceType::Int64) {
coordinates_int64_x = new long long[config.cities_number];
coordinates_int64_y = new long long[config.cities_number];
}
distance_double = new double[config.cities_number * config.cities_number];
if (config.distance_type == DistanceType::Int32) {
distance_int32 = new int[config.cities_number * config.cities_number];
}
if (config.distance_type == DistanceType::Int64) {
distance_int64 = new long long[config.cities_number * config.cities_number];
}
if (config.use_heat_map_as_initial_weights) {
heat_map = new double[config.cities_number * config.cities_number];
}
weight = new double[config.cities_number * config.cities_number];
total_weight = new double[config.cities_number];
potential = new double[config.cities_number * config.cities_number];
candidates = new int[config.cities_number * config.candidates_number];
pairs = new int[config.cities_number]; // because currently we have a random k opt depth change option
saved_pairs = new int[config.cities_number];
chosen_times = new long long[config.cities_number * config.cities_number];
for (int i = 0; i < config.cities_number * config.cities_number; ++i) {
chosen_times[i] = 0;
}
path = new City[config.cities_number];
best_path = new City[config.cities_number];
solution = new int[config.cities_number];
}
~Context() {
delete[] coordinates_double_x;
delete[] coordinates_double_y;
if (coordinates_int32_x) { delete[] coordinates_int32_x; }
if (coordinates_int32_y) { delete[] coordinates_int32_y; }
if (coordinates_int64_x) { delete[] coordinates_int64_x; }
if (coordinates_int64_y) { delete[] coordinates_int64_y; }
delete[] distance_double;
if (distance_int32) { delete[] distance_int32; }
if (distance_int64) { delete[] distance_int64; }
if (heat_map) { delete[] heat_map; }
delete[] weight;
delete[] total_weight;
delete[] potential;
delete[] candidates;
delete[] pairs;
delete[] saved_pairs;
delete[] chosen_times;
delete[] path;
delete[] best_path;
delete[] solution;
}
};
void convert_solution_to_path(const Config& config, Context& context) {
for (int i = 0; i < config.cities_number; ++i) {
int current_city = context.solution[i];
context.path[current_city].prev = context.solution[(i + config.cities_number - 1) % config.cities_number];
context.path[current_city].next = context.solution[(i + 1) % config.cities_number];
}
}
void convert_path_to_solution(const Config& config, Context& context) {
int current_city = 0;
for (int i = 0; i < config.cities_number; ++i) {
context.solution[i] = current_city;
current_city = context.path[current_city].next;
}
}
void store_path_as_best(const Config& config, Context& context) {
for (int i = 0; i < config.cities_number; ++i) {
context.best_path[i].prev = context.path[i].prev;
context.best_path[i].next = context.path[i].next;
}
if (config.distance_type == DistanceType::Double) {
context.best_path_distance_double = context.path_distance_double;
}
if (config.distance_type == DistanceType::Int32) {
context.best_path_distance_int32 = context.path_distance_int32;
}
if (config.distance_type == DistanceType::Int64) {
context.best_path_distance_int64 = context.path_distance_int64;
}
}
void restore_best_path(const Config& config, Context& context) {
for (int i = 0; i < config.cities_number; ++i) {
context.path[i].prev = context.best_path[i].prev;
context.path[i].next = context.best_path[i].next;
}
}
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