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#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("hamilton.in");
ofstream fout("hamilton.out");
using VI = vector<int>;
using VP = vector<pair<int, int>>;
const int MaxN = 18;
const int Inf = 0x3f3f3f3f;
int N, M; // N = nr. de noduri, M = nr. de muchii
vector<VP> G, rG; // G = graful, rG = graful inversat
int D[1<<MaxN][MaxN]; // D[mask][i] = costul minim daca iau bitii marcati in mask, incep ciclul cu nodul 1 si ultimul nod vizitat este i;
int res; // rezultatul (costul minim al unui ciclu hamiltonian)
void Read(); // citesc graful
void Hamilton(); // fac dinamica pt. ciclul hamiltonian de cost minim
void GetResult(); // caut rezultatul res
int main()
{
Read();
Hamilton();
GetResult();
if ( res < Inf )
fout << res;
else
fout << "Nu exista solutie";
fin.close();
fout.close();
return 0;
}
void Read()
{
fin >> N >> M;
G = rG = vector<VP>(N);
int x, y, z;
while (M--)
{
fin >> x >> y >> z;
G[x].push_back({y, z});
rG[y].push_back({x, z});
}
}
void Hamilton()
{
for (int i = 0; i < (1 << N); ++i)
for (int j = 0; j < N; ++j)
D[i][j] = Inf;
D[1][0] = 0;
for (int mask = 3; mask < (1 << N); mask += 2)
for (int j = 1; j < N; ++j)
{
if ( !(mask & (1 << j)) )
continue;
int k, c;
for (const auto& x : rG[j])
{
k = x.first; // nodul precedent lui j
c = x.second; // costul intre acel nod si j
if ( j == k || !(mask & (1 << k)) )
continue;
D[mask][j] = min(D[mask][j], D[mask ^ (1 << j)][k] + c);
// cout << mask << ' ' << j << ' ' << D[mask][j]; cin.get();
}
}
}
void GetResult()
{
res = Inf;
for (int j = 0; j < N; ++j)
{
for (const auto& x : G[j])
if ( x.first == 0 )
{
res = min(res, D[(1 << N) - 1][j] + x.second);
break;
}
}
}