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#include <fstream>
#include <vector>
#include <bitset>
#define INF 0x3f3f3f3f
using namespace std;
vector<vector<int>> DP, Cost, Graph;
vector<bitset<18>> Computed;
int dynamic(int mask, int to)
{
if (Computed[mask][to])
return DP[mask][to];
if (mask == 0)
return INF;
for (auto from: Graph[to])
if (mask & (1<<from))
if(DP[mask][to] > dynamic(mask ^ (1<<to), from) + Cost[from][to])
DP[mask][to] = dynamic(mask ^ (1<<to), from) + Cost[from][to];
Computed[mask][to] = true;
return DP[mask][to];
}
int main()
{
ifstream fin("hamilton.in");
ofstream fout("hamilton.out");
fin.sync_with_stdio(false);
fin.tie(0);
int N, M;
fin >> N >> M;
Graph.resize(N);
Cost.resize(N);
fill(Cost.begin(), Cost.end(), vector<int>(N, 0));
for (int i = 0; i < M; ++i) {
int from, to, cost;
fin >> from >> to >> cost;
Graph[to].emplace_back(from);
Cost[from][to] = cost;
}
DP.resize(1<<N);
Computed.resize(1<<N);
fill(DP.begin(), DP.end(), vector<int>(N, INF));
// assume we start the cycle in node 0;
DP[1<<0][0] = 0; // we visited 0th node, and the cost is 0
Computed[1<<0][0] = true;
int best = INF;
for (auto from : Graph[0]) { // the closing edge
// start in `0`, go through all nodes and finish in `from` and close with edge {from,0}
if (best > dynamic((1<<N)-1, from) + Cost[from][0])
best = dynamic((1<<N)-1, from) + Cost[from][0];
}
if (best != INF)
fout << best << "\n";
else
fout << "Nu exista solutie\n";
return 0;
}