vector < int > edg[N];

void AddEdge(int a , int b)
{
    edg[a].push_back(b);
}


int main()
{
    /// problem: https://codeforces.com/gym/101992/problem/H
    int u , L , K;

    vector < pair < int , pair < int , int > > > edges;

    while(m--){
        int a , b , c;
        cin>>a>>b>>c;
        AddEdge(a , b);
        AddEdge(b , a);
        edges.push_back({c , {a,b}});
    }

    bfs(u);

    sort(edges.begin() , edges.end());
    reverse(edges.begin() , edges.end());
    for(auto p:edges){
        int w = p.first , a = p.second.first , b = p.second.second;
        if(min(dis[a] , dis[b]) < K){
            cout<<w<<endl;
            return 0;
        }
    }
}