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#include <fstream>
#include <vector>
#include <algorithm>
#include <queue>
#include <cassert>
using namespace std;
const int kNmax = 50005;
ofstream fout("bellmanford.out");
class Task {
public:
void solve() {
read_input();
print_output(get_result());
}
private:
int n;
int m;
int source;
vector<pair<int, int> > adj[kNmax];
void read_input() {
ifstream fin("bellmanford.in");
fin >> n >> m >> source;
for (int i = 1, x, y, w; i <= m; i++) {
fin >> x >> y >> w;
adj[x].push_back(make_pair(y, w));
}
fin.close();
}
vector<int> get_result() {
/*
TODO: Gasiti distantele minime de la nodul source la celelalte noduri
folosind BellmanFord pe graful orientat cu n noduri, m arce stocat in adj.
d[node] = costul minim / lungimea minima a unui drum de la source la nodul
node;
d[source] = 0;
d[node] = -1, daca nu se poate ajunge de la source la node.
Atentie:
O muchie este tinuta ca o pereche (nod adiacent, cost muchie):
adj[x][i].first = nodul adiacent lui x,
adj[x][i].second = costul.
In cazul in care exista ciclu de cost negativ, returnati un vector gol:
return vector<int>();
*/
int i, j;
source = 1;
vector<int> d(n + 1, 1 << 30);
vector<int> v(n + 1, 0);
d[source] = 0;
queue<int> q;
while (!q.empty()) {
int node = q.front();
q.pop();
for (auto& i : adj[node]) {
if (d[i.first] > d[node] + i.second) {
d[i.first] = d[node] + i.second;
q.push(i.first);
}
}
}
for (i = 1; i <= n; i++) {
if (i != source && d[i] == (1 << 30)) {
d[i] = -1;
}
}
return d;
}
void print_output(vector<int> result) {
if (result.size() == 0) {
fout << "Ciclu negativ!\n";
} else {
for (int i = 1; i <= n; i++) {
fout << result[i] << ' ';
}
fout << '\n';
}
fout.close();
}
};
int main() {
Task *task = new Task();
task->solve();
delete task;
return 0;
}