// includes #include using namespace std; // macros #define pb emplace_back #define mk make_pair #define FOR(i, a, b) for(int i=(a);i<(b);++i) #define rep(i, n) FOR(i, 0, n) #define rrep(i, n) for(int i=((int)(n)-1);i>=0;i--) #define irep(itr, st) for(auto itr = (st).begin(); itr != (st).end(); ++itr) #define irrep(itr, st) for(auto itr = (st).rbegin(); itr != (st).rend(); ++itr) #define all(x) (x).begin(),(x).end() #define sz(x) ((int)(x).size()) #define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end()) #define bit(n) (1LL<<(n)) // functions template bool chmax(T &a, const T &b){if(a < b){a = b; return 1;} return 0;} template bool chmin(T &a, const T &b){if(a > b){a = b; return 1;} return 0;} template istream &operator>>(istream &is, vector &vec){for(auto &v: vec)is >> v; return is;} template ostream &operator<<(ostream &os, const vector& vec){for(int i = 0; i < vec.size(); i++){ os << vec[i]; if(i + 1 != vec.size())os << " ";} return os;} template ostream &operator<<(ostream &os, const set& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const unordered_set& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const multiset& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const unordered_multiset& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;} template ostream &operator<<(ostream &os, const pair &p){os << p.first << " " << p.second; return os;} template ostream &operator<<(ostream &os, const map &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;} template ostream &operator<<(ostream &os, const unordered_map &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;} // types using ll = long long int; using P = pair; // constants const int inf = 1e9; const ll linf = 1LL << 50; const double EPS = 1e-10; const int mod = 1000000007; const int dx[4] = {-1, 0, 1, 0}; const int dy[4] = {0, -1, 0, 1}; // io struct fast_io{ fast_io(){ios_base::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(20);} } fast_io_; template struct Graph { int n; vector > > edge; vector dis; Graph(int n): n(n) { edge.resize(n); dis.resize(n); } void dijkstra(int s){ dijkstra(s, 0); } T dijkstra(int s, int t){ // initialize fill(dis.begin(), dis.end(), -1); vector used(n, false); dis[s] = 0; // dijkstra priority_queue, vector >, greater > > q; q.push(make_pair(0, s)); while(!q.empty()){ pair p = q.top(); q.pop(); int at = p.second; T distance = p.first; if(used[at])continue; used[at] = true; for(auto itr = edge[at].begin(); itr != edge[at].end(); ++itr){ int to = (*itr).first; T cost = (*itr).second; if(used[to])continue; if(dis[to] == -1 || dis[to] > distance + cost){ q.push(make_pair(distance + cost, to)); dis[to] = distance + cost; } } } return dis[t]; } void adde(int at, int to, T cost){ edge[at].push_back(make_pair(to, cost)); } [[deprecated("This function takes O(|edge[at]|).")]] void remove(int at, int to){ int index = -1; for(int i = 0; i < edge[at].size(); i++){ if(edge[at][i].first == to){ index = i; break; } } edge[at].erase(edge[at].begin() + index); } }; using GraphI = Graph; using GraphL = Graph; using GraphD = Graph; int d[201][201]; int main(int argc, char const* argv[]) { int n, m, s, g; cin >> n >> m >> s >> g; GraphL gr(n); rep(i, m){ int a, b, c; cin >> a >> b >> c; gr.adde(a, b, c); gr.adde(b, a, c); d[a][b] = c; d[b][a] = c; } gr.dijkstra(g); ll all = gr.dis[s]; int curr = s; ll curd = 0; vector res; res.pb(s); while(curr != g){ rep(i, n){ if(d[curr][i] == 0)continue; int tmp = curd + d[curr][i] + gr.dis[i]; if(tmp == all){ curd += d[curr][i]; res.pb(i); curr = i; break; } } } cout << res << endl; return 0; }