Pagini recente » Cod sursa (job #2631654) | Cod sursa (job #1065513) | Cod sursa (job #473893) | Cod sursa (job #2467713) | Cod sursa (job #605444)
Cod sursa(job #605444)
# include <fstream>
# include <vector>
# include <set>
# include <cstdlib>
using namespace std;
vector < pair <int, int> > LIST[50100];
int n, m, x, y, cost, dist[50100], ap[50100], apQ[50100];
set <pair <int, int> > st;
ifstream f ("bellmanford.in");
ofstream g ("bellmanford.out");
void bellmanford ()
{
for (int i = 1; i <= n; ++i) dist[i] = 2000000000;
st.insert (make_pair (0, 1)); // cost, nod
dist[1] = 0;
for (; st.size () > 0; )
{
int cost = st.begin () -> first, nod = st.begin () -> second;
st.erase ((*st.begin ()));
apQ[nod] = 0;
for (vector < pair <int, int> > :: iterator it = LIST[nod].begin (); it != LIST[nod].end (); ++it)
{
if (dist[it -> second] > dist[nod] + it -> first)
{
dist[it -> second] = dist[nod] + it -> first;
if (!apQ[it -> second])
{
if (ap[it -> second] > n)
{
g << "Ciclu negativ!";
exit (0);
}
else
{
st.insert (*it);
ap[it -> second] = ap[nod] + 1;
apQ[it -> second] = 1;
}
}
}
}
}
}
int main ()
{
f >> n >> m;
for (int i = 1; i <= m; ++i)
{
f >> x >> y >> cost;
LIST[x].push_back (make_pair (cost, y));
}
bellmanford ();
for (int i = 2; i <= n; ++i)
g << dist[i] << ' ';
return 0;
g.close ();
}