33 lines
743 B
C++
33 lines
743 B
C++
#include "sa.hpp"
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#include <cmath>
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auto sa::solution::simulated_annealing(int capacity, const std::vector<long long> &items,
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const double alpha, double temp,
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const double temp_min)->sa::solution
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{
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sa::solution best(items, capacity);
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sa::solution prev = best;
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int iteration = 0;
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while (temp > temp_min) {
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iteration++;
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sa::solution neighbor(prev, iteration);
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neighbor.setneighbor();
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long long diff = neighbor.fitness - prev.fitness;
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if (diff < 0 || rng::random_double<0, 1>() / temp < 0.8) {
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swap(prev, neighbor);
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}
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temp *= alpha;
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if (prev.fitness < best.fitness) {
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best = prev;
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}
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}
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best.setiterations(iteration);
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return best;
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}
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