#include <bits/stdc++.h>
using namespace std;

#define      PSB         push_back
#define      ll          long long
#define      MP          make_pair
#define      FastIO      ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
constexpr ll mod = 1e9  + 7;
const ll N=3e6+5;

int n,m;
const int INF = 1000000000;
vector<vector<pair<int, int>>> adj;
//vector<int> d(N),p(N);

void dijkstra(int s, vector<int> & d, vector<int> & p) {
    int n = adj.size();
    d.assign(n, INF);
    p.assign(n, -1);

    d[s] = 0;
    using pii = pair<int, int>;
    priority_queue<pii, vector<pii>, greater<pii>> q;
    q.push({0, s});
    while (!q.empty()) {
        int v = q.top().second;
        int d_v = q.top().first;
        q.pop();
        if (d_v != d[v])
            continue;

        for (auto edge : adj[v]) {
            int to = edge.first;
            int len = edge.second;

            if (d[v] + len < d[to]) {
                d[to] = d[v] + len;
                p[to] = v;
                q.push({d[to], to});
            }
        }
    }
}

int main(){
  FastIO

  //int n,m;
  cin>>n>>m;

  for(int i=0;i<m;i++){
    int a,b,w; cin>>a>>b>>w;
    --a,--b;
    adj[a].PSB(MP(b,w));
    adj[b].PSB(MP(a,w));
  }


  //dijkstra(1, d, p);



  return 0;
}