#include <iostream>
#include <vector>
#include <utility>
#include <limits>
#include <algorithm>
#include <tuple>

extern void three_opt(std::vector<uint>& tour,
		const double (&dist_matrix) [1577][1577],
		double& sh_dist);
extern std::ostream& operator<< (std::ostream& out, std::vector<uint> a);