#include <bits/stdc++.h>
using namespace std;
const long long oo = 1e18;
vector<int> dinh;
int nn;
long long n, m, k, kc[801][801];
vector<pair<long long, pair<long long, long long>>> e;
void compress() {
  sort(dinh.begin(), dinh.end());
  dinh.resize(unique(dinh.begin(), dinh.end()) - dinh.begin());
  nn = dinh.size();
  for (long long i = 0; i <= nn - 1; i++)
    for (long long j = 0; j <= nn - 1; j++) kc[i][j] = oo;
  for (long long i = 0; i <= nn - 1; i++) kc[i][i] = 0;
  for (long long i = 0; i <= min(m, k) - 1; i++) {
    long long first =
        lower_bound(dinh.begin(), dinh.end(), e[i].second.first) - dinh.begin();
    long long second =
        lower_bound(dinh.begin(), dinh.end(), e[i].second.second) -
        dinh.begin();
    kc[first][second] = kc[second][first] = min(kc[first][second], e[i].first);
  }
}
void floyd() {
  for (long long k = 0; k <= nn - 1; k++)
    for (long long first = 0; first <= nn - 1; first++)
      for (long long second = 0; second <= nn - 1; second++)
        kc[first][second] =
            min(kc[first][second], kc[first][k] + kc[k][second]);
}
int main() {
  cin >> n >> m >> k;
  for (long long i = 0; i <= m - 1; i++) {
    long long first, second, w;
    cin >> first >> second >> w;
    e.push_back({w, {first - 1, second - 1}});
  }
  sort(e.begin(), e.end());
  for (long long i = 0; i <= min(m, k) - 1; i++) {
    dinh.push_back(e[i].second.first);
    dinh.push_back(e[i].second.second);
  }
  compress();
  floyd();
  vector<long long> res;
  for (long long i = 0; i <= nn - 1; i++)
    for (long long j = 0; j <= i - 1; j++) res.push_back(kc[i][j]);
  sort(res.begin(), res.end());
  cout << res[k - 1];
  return 0;
}
