#include <bits/stdc++.h>
long long int const MOD = 1000000007;
long long int const N = 1000005;
long long int const LN = 20;
long long int const inf = 8e18;
using namespace std;
long long int n, m, a[N];
vector<pair<long long int, long long int> > v[N];
struct data {
  long long int d, second, prev, idx;
  data(long long int d, long long int second, long long int prev,
       long long int idx) {
    this->d = d;
    this->second = second;
    this->prev = prev;
    this->idx = idx;
  }
  bool operator<(data other) const {
    if (d != other.d) return d < other.d;
    if (second != other.second) return second < other.second;
    if (prev != other.prev) return prev < other.prev;
    if (idx != other.idx) return idx < other.idx;
    return 0;
  }
};
int main() {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  long long int n, m, k;
  cin >> n >> m >> k;
  for (long long int i = 1; i <= m; i++) {
    long long int a, b, c;
    cin >> a >> b >> c;
    v[a].push_back({c, b});
    v[b].push_back({c, a});
  }
  for (long long int i = 1; i <= n; i++) sort(v[i].begin(), v[i].end());
  set<pair<long long int, long long int> > st;
  set<data> q;
  for (long long int i = 1; i <= n; i++) {
    st.insert({i, i});
    q.insert(data(v[i][0].first, i, i, 0));
  }
  k = 2 * k;
  while (!q.empty()) {
    data cur = *q.begin();
    q.erase(cur);
    long long int nxt = v[cur.prev][cur.idx].second;
    if (st.find({cur.second, nxt}) == st.end()) {
      st.insert({cur.second, nxt});
      k--;
      if (k == 0) {
        cout << cur.d << '\n';
        return 0;
      }
      q.insert(data(cur.d + v[nxt][0].first, cur.second, nxt, 0));
    }
    if (cur.idx + 1 < v[cur.prev].size())
      q.insert(data(
          cur.d - v[cur.prev][cur.idx].first + v[cur.prev][cur.idx + 1].first,
          cur.second, cur.prev, cur.idx + 1));
  }
  return 0;
}
