#include <bits/stdc++.h>
using namespace std;
int ROW[] = {+0, +0, -1, +1};
int COL[] = {+1, -1, +0, +0};
int X[] = {+0, +0, +1, -1, -1, +1, -1, +1};
int Y[] = {-1, +1, +0, +0, +1, +1, -1, -1};
int KX[] = {-2, -2, -1, -1, 1, 1, 2, 2};
int KY[] = {-1, 1, -2, 2, -2, 2, -1, 1};
vector<int> adj[200005];
set<pair<long long, pair<int, int> > > pq;
map<pair<int, int>, long long> val;
map<pair<int, int>, bool> vis;
int k;
void dijkstra() {
  long long ans, tt;
  int cnt = k;
  while (true) {
    pair<long long, pair<int, int> > q = *pq.rbegin();
    tt = q.first;
    pair<long long, pair<int, int> > p = *pq.begin();
    pq.erase(pq.begin());
    ans = p.first;
    if (vis[p.second]) continue;
    vis[p.second] = true;
    vis[{p.second.second, p.second.first}] = true;
    k--;
    if (!k) break;
    for (auto x : adj[p.second.first]) {
      if (x == p.second.second) continue;
      long long temp = val[{p.second.first, x}] + p.first;
      if (pq.size() > cnt && temp >= tt) continue;
      if (val.find({p.second.second, x}) == val.end()) {
        val[{p.second.second, x}] = temp;
        val[{x, p.second.second}] = temp;
        pq.insert({temp, {x, p.second.second}});
      } else if (temp < val[{p.second.second, x}]) {
        val[{p.second.second, x}] = temp;
        val[{x, p.second.second}] = temp;
        pq.insert({temp, {x, p.second.second}});
      }
    }
    for (auto x : adj[p.second.second]) {
      if (x == p.second.first) continue;
      long long temp = val[{p.second.second, x}] + p.first;
      if (pq.size() > cnt && temp >= tt) continue;
      if (val.find({p.second.first, x}) == val.end()) {
        val[{p.second.first, x}] = temp;
        val[{x, p.second.first}] = temp;
        pq.insert({temp, {x, p.second.first}});
      } else if (temp < val[{p.second.first, x}]) {
        val[{p.second.first, x}] = temp;
        val[{x, p.second.first}] = temp;
        pq.insert({temp, {x, p.second.first}});
      }
    };
  }
  cout << ans << endl;
}
int main() {
  int n, m, x, y, w, q, des, st, p;
  cin >> n >> m >> k;
  for (int i = 0; i < m; i++) {
    cin >> x >> y >> w;
    pq.insert({w, {x, y}});
  }
  while (pq.size() > 400) pq.erase(*pq.rbegin());
  for (auto it : pq) {
    val[it.second] = it.first;
    val[{it.second.second, it.second.first}] = it.first;
    adj[it.second.first].push_back(it.second.second);
    adj[it.second.second].push_back(it.second.first);
  }
  dijkstra();
  ;
  return 0;
}
