#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
namespace my{
#define eb emplace_back
#define LL(...) ll __VA_ARGS__;lin(__VA_ARGS__)
#define VV(n,...) vec<ll>__VA_ARGS__;setsize({n},__VA_ARGS__);vin(__VA_ARGS__)
#define FO(n) for(ll ij=n;ij-->0;)
#define FOR(i,...) for(auto[i,i##stop,i##step]=range(0,__VA_ARGS__);i<i##stop;i+=i##step)
#define fo(i,...) FO##__VA_OPT__(R)(i __VA_OPT__(,__VA_ARGS__))
#define fe(a,i,...) for(auto&&__VA_OPT__([)i __VA_OPT__(,__VA_ARGS__]):a)
#define single_testcase void solve();}int main(){my::io();my::solve();}namespace my{
void io(){cin.tie(nullptr)->sync_with_stdio(0);cout<<fixed<<setprecision(15);}
using ld=long double;
using ll=long long;
constexpr auto range(bool s,auto...a){array<ll,3>r{0,0,1};ll I=0;((r[I++]=a),...);if(!s&&I==1)swap(r[0],r[1]);r[0]-=s;if(s)r[2]*=-1;return r;}
constexpr ld ee=1e-12;
constexpr char newline=10;
constexpr char space=32;
constexpr auto abs(auto x){return x<0?-x:x;}
auto ceil(auto x,auto y){if(y<0)x=-x,y=-y;return x<=0?x/y:(x-1)/y+1;}
bool amin(auto&a,const auto&b){return b<a?a=b,1:0;}
auto max(auto...a){return max(initializer_list<common_type_t<decltype(a)...>>{a...});}

template<class A,class B>struct pair{
  A a;B b;
  pair()=default;
  pair(A a,B b):a(a),b(b){}
  pair(const std::pair<A,B>&p):a(p.first),b(p.second){}
  auto operator<=>(const pair&)const=default;
  pair operator+(const pair&p)const{return{a+p.a,b+p.b};}
  friend istream&operator>>(istream&i,pair&p){return i>>p.a>>p.b;}
  friend ostream&operator<<(ostream&o,const pair&p){return o<<p.a<<space<<p.b;}
};

template<class T,class U>ostream&operator<<(ostream&o,const std::pair<T,U>&p){return o<<p.first<<space<<p.second;}

template<class T>struct queue:std::queue<T>{
  queue(const initializer_list<T>&a={}){fe(a,e)this->emplace(e);}
  queue(const vector<T>&a){fe(a,e)this->emplace(e);}
  ll size()const{return std::queue<T>::size();}
  T pop(){T r=this->front();std::queue<T>::pop();return r;}
  friend ostream&operator<<(ostream&o,queue q){while(q.size())o<<q.pop()<<string(q.size()>0,space);return o;}
};

template<class T,class F>struct priority_queue:std::priority_queue<T,vector<T>,F>{
  priority_queue(const initializer_list<T>&a={}){fe(a,e)this->emplace(e);}
  priority_queue(const vector<T>&a){fe(a,e)this->emplace(e);}
  ll size()const{return std::priority_queue<T,vector<T>,F>::size();}
  T pop(){T r=this->top();std::priority_queue<T,vector<T>,F>::pop();return r;}
  friend ostream&operator<<(ostream&o,priority_queue q){while(q.size())o<<q.pop()<<string(q.size()>0,space);return o;}
};
template<class T>using min_heap=priority_queue<T,greater<T>>;

template<ll k>auto pack_kth(const auto&...a){return get<k>(make_tuple(a...));}
template<class T,size_t...I>auto pack_slice_impl(index_sequence<I...>, const auto&...a){return array<T,sizeof...(I)>{get<I>(forward_as_tuple(a...))...};}
template<class T,size_t n>auto pack_slice(const auto&...a){return pack_slice_impl<T>(make_index_sequence<n>{},a...);}

template<class V>concept vectorial=is_base_of_v<vector<typename V::value_type>,V>;
template<class T>struct vec_attr{using core_type=T;static constexpr int rank=0;};
template<vectorial V>struct vec_attr<V>{using core_type=typename vec_attr<typename V::value_type>::core_type;static constexpr int rank=vec_attr<typename V::value_type>::rank+1;};
template<class T>using core_t=vec_attr<T>::core_type;
template<class V>istream&operator>>(istream&i,vector<V>&v){fe(v,e)i>>e;return i;}
template<class V>ostream&operator<<(ostream&o,const vector<V>&v){fe(v,e)o<<e<<string(&e!=&v.back(),vectorial<V>?newline:space);return o;}

template<class V>struct vec:vector<V>{
  using vector<V>::vector;
  vec(const vector<V>&v){vector<V>::operator=(v);}

  template<class...A>requires(sizeof...(A)>=3)vec(A...a){const ll n=sizeof...(a)-1;auto t=pack_slice<ll,n>(a...);ll s[n];fo(i,n)s[i]=t[i];*this=make_vec(s,pack_kth<n>(a...));}
  template<class T,ll n,ll i=0>static auto make_vec(const ll(&s)[n],T x){if constexpr(i==n-1)return vec<T>(s[i],x);else{auto X=make_vec<T,n,i+1>(s,x);return vec<decltype(X)>(s[i],X);}}

  vec&operator^=(const vec&u){this->insert(this->end(),u.begin(),u.end());return*this;}
  vec operator^(const vec&u)const{return vec{*this}^=u;}
  vec&operator+=(const vec&u){vec&v=*this;fo(i,v.size())v[i]+=u[i];return v;}
  vec&operator-=(const vec&u){vec&v=*this;fo(i,v.size())v[i]-=u[i];return v;}
  vec operator+(const vec&u)const{return vec{*this}+=u;}
  vec operator-(const vec&u)const{return vec{*this}-=u;}
  vec&operator++(){fe(*this,e)++e;return*this;}
  vec&operator--(){fe(*this,e)--e;return*this;}
  vec operator-()const{vec v=*this;fe(v,e)e=-e;return v;}

  ll size()const{return vector<V>::size();}

  auto scan(const auto&f)const{pair<core_t<V>,bool>r{};fe(*this,e)if constexpr(!vectorial<V>)r.b?f(r.a,e),r:r={e,1};else if(auto s=e.scan(f);s.b)r.b?f(r.a,s.a),r:r=s;return r;}
  auto max()const{return scan([](auto&a,const auto&b){a<b?a=b:0;}).a;}
};
template<ll rank,class T>struct tensor_helper{using type=vec<typename tensor_helper<rank-1,T>::type>;};
template<class T>struct tensor_helper<0,T>{using type=T;};
template<ll rank,class T>using tensor=typename tensor_helper<rank,T>::type;
template<class...A>requires(sizeof...(A)>=2)vec(A...a)->vec<tensor<sizeof...(a)-2,remove_reference_t<decltype(get<sizeof...(a)-1>(declval<tuple<A...>>()))>>>;
vec(ll)->vec<ll>;

template<ll n,class...A>void setsize(const ll(&l)[n],A&...a){((a=vec<void*>::make_vec(l,core_t<A>{})),...);}

template<bool is_negative=false>struct infinity{
  template<integral T>constexpr operator T()const{return numeric_limits<T>::max()*(1-is_negative*2);}
  template<floating_point T>constexpr operator T()const{return static_cast<ll>(*this);}
  template<class T>constexpr bool operator==(T x)const{return static_cast<T>(*this)==x;}
  constexpr auto operator-()const{return infinity<!is_negative>();}
  template<class A,class B>constexpr operator pair<A,B>()const{return pair<A,B>{*this,*this};}
};
constexpr infinity oo;

void lin(auto&...a){(cin>>...>>a);}
void vin(auto&...a){fo(i,(a.size()&...))(cin>>...>>a[i]);}
template<char c=space>void pp(const auto&...a){ll n=sizeof...(a);((cout<<a<<string(--n>0,c)),...);cout<<newline;}

void dec(auto&...a){((--a),...);}
template<class T>auto binary_search(const auto&f,T o,T x){
  if(is_floating_point_v<T>)fo(log2((abs(o-x)/ee))+6)(f((o+x)/2)?o:x)=(o+x)/2;
  else while(abs(o-x)>1)(f((o+x)/2)?o:x)=(o+x)/2;
  return o;
}
auto binary_searchll(auto f,ll o,ll x){return binary_search<ll>(f,o,x);}

template<class WT>struct edge{
  ll from,to;
  WT wt;
  ll id;
  edge()=default;
  edge(ll from,ll to,WT wt=1,ll id=-1):from(from),to(to),wt(wt),id(id){}
  auto operator<=>(const edge&e)const{return wt<=>e.wt;}
  friend ostream&operator<<(ostream&o,const edge&e){return o<<"(to "<<e.to<<", wt "<<e.wt<<",id "<<e.id<<")";}
};

template<class WT>struct graph{
  vec<vec<edge<WT>>>edges;

  graph()=default;
  graph(ll n):edges(n){}

  decltype(auto)operator[](ll i){return edges[i];}
  decltype(auto)operator[](ll i)const{return edges[i];}

  ll size()const{return edges.size();}

  friend ostream&operator<<(ostream&o,const graph&g){
    fo(u,g.size()){
      o<<"from "<<u<<": ";
      fo(j,g[u].size())o<<g[u][j]<<string(j!=g[u].size()-1,space);
      o<<newline;
    }
    return o;
  }

  void add_edges(const vec<ll>&p){fo(i,p.size())if(p[i]!=-1)edges[p[i]].eb(p[i],i,1,i);}
  void add_edges(const vec<ll>&a,const vec<ll>&b){fo(i,a.size())edges[a[i]].eb(a[i],b[i],1,i);}
  void add_edges(const vec<ll>&a,const vec<ll>&b,const vec<WT>&w){fo(i,a.size())edges[a[i]].eb(a[i],b[i],w[i],i);}
  void add_edges(const vec<edge<WT>>&es){fe(es,e)edges[e.from].eb(e);}
};

template<class WT>struct rooted_tree:graph<WT>{
  vec<edge<WT>>rev_edge;
  ll r;
  rooted_tree(ll n,ll r):graph<WT>(n),rev_edge(n,{-1,-1,WT(),-1}),r(r){}

  void add_edge_and_set_rev_edge(const edge<WT>&e){
    this->edges[e.from].eb(e);
    this->rev_edge[e.to]=e;
  }

  auto dist_enumerate()const{
    vec<WT>res(this->size());
    fe(bfs_order(),u)fe(this->edges[u],e)res[e.to]=res[u]+e.wt;
    return res;
  }

  auto bfs_order()const{
    vec<ll>ord;
    queue<ll>q{r};
    while(q.size()){
      ll u=q.pop();
      ord.eb(u);
      fe(this->edges[u],e)q.emplace(e.to);
    }
    return ord;
  }
};

template<class WT>auto dijkstra_tree(const graph<WT>&g,ll s){
  rooted_tree<WT>tree(g.size(),s);
  vec<WT>dist(g.size(),oo);
  dist[s]=WT{};

  vec<bool>used(g.size());
  min_heap<pair<WT,edge<WT>>>q{{WT{},{-1,s,WT{},-1}}};
  while(q.size()){
    auto[du,pu]=q.pop();
    ll u=pu.to;
    if(dist[u]<du)continue;
    if(used[u])continue;
    used[u]=1;

    if(pu.from!=-1)tree.add_edge_and_set_rev_edge(pu);

    fe(g[u],e){
      if(amin(dist[e.to],dist[u]+e.wt)){
        assert(!used[e.to]);
        q.emplace(dist[e.to],e);
      }
    }
  }
  return tree;
}

ll f(ll D,ll x){
  return max(ceil(D,x)-1,0);
}

single_testcase
void solve(){
  LL(N,M,K);
  VV(M,a,b,c);dec(a,b);

  pp(binary_searchll([&](ll X){
    graph<ll>g(N);
    vec f(M);
    fo(i,M)f[i]=(c[i]>X);
    g.add_edges(a,b,f);
    g.add_edges(b,a,f);
    return dijkstra_tree(g,0).dist_enumerate()[N-1]<K;
  },c.max(),-1));
}}