#include <bits/stdc++.h>
using namespace std;
mt19937_64 rang(
    chrono::high_resolution_clock::now().time_since_epoch().count());
int rng(int lim) {
  uniform_int_distribution<int> uid(0, lim - 1);
  return uid(rang);
}
const long long INF = 1e18;
const int mod = 1e9 + 7;
long long n, m, k;
void solve() {
  cin >> n >> m >> k;
  if (k <= m) {
    vector<pair<long long, pair<long long, long long>>> v;
    for (long long i = 0; i < m; i++) {
      long long x, y, w;
      cin >> x >> y >> w;
      v.push_back({w, {x, y}});
    }
    sort(v.begin(), v.end());
    map<long long, long long> make_pair;
    for (long long i = 0; i < k; i++) {
      make_pair[v[i].second.first] = 1;
      make_pair[v[i].second.second] = 1;
    }
    long long id = 0;
    for (auto p : make_pair) make_pair[p.first] = ++id;
    n = make_pair.size();
    long long d[n + 1][n + 1];
    for (long long i = 1; i <= n; i++) {
      for (long long j = 1; j <= n; j++) {
        if (i == j)
          d[i][j] = 0;
        else
          d[i][j] = INF;
      }
    }
    for (long long i = 0; i < k; i++) {
      long long x = v[i].second.first, y = v[i].second.second;
      if (make_pair.count(x) && make_pair.count(y)) {
        d[make_pair[x]][make_pair[y]] = v[i].first;
        d[make_pair[y]][make_pair[x]] = v[i].first;
      }
    }
    for (long long k = 1; k <= n; k++) {
      for (long long i = 1; i <= n; i++) {
        for (long long j = 1; j <= n; j++) {
          d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
        }
      }
    }
    vector<long long> t;
    for (long long i = 1; i <= n; i++) {
      for (long long j = 1; j <= n; j++) {
        if (i < j) t.push_back(d[i][j]);
      }
    }
    sort(t.begin(), t.end());
    cout << t[k - 1] << "\n";
  } else {
    long long d[n + 1][n + 1];
    for (long long i = 1; i <= n; i++) {
      for (long long j = 1; j <= n; j++) {
        if (i == j)
          d[i][j] = 0;
        else
          d[i][j] = INF;
      }
    }
    for (long long i = 0; i < m; i++) {
      long long u, v, w;
      cin >> u >> v >> w;
      d[u][v] = w;
      d[v][u] = w;
    }
    for (long long k = 1; k <= n; k++) {
      for (long long i = 1; i <= n; i++) {
        for (long long j = 1; j <= n; j++) {
          d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
        }
      }
    }
    vector<long long> t;
    for (long long i = 1; i <= n; i++) {
      for (long long j = 1; j <= n; j++) {
        if (i < j) t.push_back(d[i][j]);
      }
    }
    sort(t.begin(), t.end());
    cout << t[k - 1] << "\n";
  }
}
int main() {
  ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
  srand(chrono::high_resolution_clock::now().time_since_epoch().count());
  int t = 1;
  while (t--) {
    solve();
  }
  return 0;
}
