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#include <chrono>
#include <iostream>
#include <fstream>
class stopwatch
{
std::chrono::high_resolution_clock::time_point start;
public:
stopwatch()
: start(std::chrono::high_resolution_clock::now())
{
}
~stopwatch()
{
auto duration = std::chrono::high_resolution_clock::now() - start;
std::cerr << std::chrono::duration_cast<std::chrono::milliseconds>(duration).count() << " ms" << std::endl;
}
};
#define NMAX 13
using namespace std;
ifstream f("damesah.in");
ofstream g("damesah.out");
int n;
int sol[NMAX];
bool column[NMAX];
bool main_diag[2 * NMAX - 1];
bool sec_diag[2 * NMAX - 1];
int no_solutions;
void n_queens_problem(int k)
{
if (k == n)
{
if (!no_solutions++)
{
for (int i = 0; i < n; ++i)
g << sol[i] + 1 << " ";
g << "\n";
}
return;
}
for (int c = 0; c < n; c++)
{
if (!column[c] && !main_diag[NMAX + k - c] && !sec_diag[k + c])
{
sol[k] = c;
column[c] = main_diag[NMAX + k - c] = sec_diag[k + c] = true;
n_queens_problem(k + 1);
column[c] = main_diag[NMAX + k - c] = sec_diag[k + c] = false;
}
}
}
int main() {
stopwatch sw;
f >> n;
n_queens_problem(0);
g << no_solutions << "\n";
return 0;
}