Cod sursa(job #2689977)

Utilizator davidcotigacotiga david davidcotiga Data 22 decembrie 2020 18:52:31
Problema Ciclu hamiltonian de cost minim Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.17 kb
#include <fstream>
#include <vector>
#include <cstring>

using namespace std;

ifstream fin("hamilton.in");
ofstream fout("hamilton.out");

const int MAXN = 20;
const int MAXX = 262150;
const int INF = 1000000000;

int N, M, Sol;
vector<int> A[MAXN];
int C[MAXX][MAXN];
int Cost[MAXN][MAXN];

int calc(int conf, int last) {
	if (C[conf][last] == -1) {
		C[conf][last] = INF;

		for (size_t i = 0; i < A[last].size(); ++i)
			if (conf & (1 << A[last][i])) {
				if (A[last][i] == 0 && conf != (1 << (last)) + 1)
					continue;
				C[conf][last] = min(C[conf][last], calc(conf ^ (1 << last), A[last][i]) + Cost[A[last][i]][last]);
			}
	}
	return C[conf][last];
}

int main() {
	Sol = INF;

	fin >> N >> M;

	for (int i = 0; i < N; ++i)
		for (int j = 0; j < N; ++j)
			Cost[i][j] = INF;

	for (int i = 1; i <= M; ++i) {
		int x, y;

		fin >> x >> y;
		A[y].push_back(x);
		fin >> Cost[x][y];
	}

	memset(C, -1, sizeof(C));

	C[1][0] = 0;

	for (size_t i = 0; i < A[0].size(); ++i)
		Sol = min(Sol, calc((1 << N) - 1, A[0][i]) + Cost[A[0][i]][0]);

	if (Sol == INF)
		fout << "Nu exista solutie\n";
	else
		fout << Sol << "\n";

	return 0;
}