#include <bits/stdc++.h>
using namespace std;
ifstream fin("dijkstra.in");
ofstream fout("dijkstra.out");
const int NMAX=50005;
const int inf=LONG_MAX;
vector<pair<int,int> >L[NMAX];
priority_queue<pair<int,int> >Q;
int n,m,dist[NMAX];
bool viz[NMAX];
inline void READ()
{
    fin>>n>>m;
    while(m--)
    {
        int nod,nod1,cost;
        fin>>nod>>nod1>>cost;
        L[nod].push_back({nod1,cost});

    }
}
inline void DIJKSTRA()
{
    for(int i=2;i<=n;i++)
        dist[i]=inf;
    Q.push({0,1});
    while(!Q.empty())
    {
        int nod=Q.top().second;
        Q.pop();
        if(!viz[nod])
        {
            viz[nod]=true;
            for(auto i:L[nod])
            {
                if(dist[i.first]>dist[nod]+i.second)
                {
                    dist[i.first]=dist[nod]+i.second;
                    Q.push({-dist[i.first],i.first});
                }
            }
        }
    }
    cout<<n<<"\n";
    for(int i=2;i<=n;i++)
        if(dist[i]==inf)
            fout<<"0 ";
    else fout<<dist[i]<<" ";
}
int main()
{
    READ();
    DIJKSTRA();
    fin.close();
    fout.close();
    return 0;
}