#include <bits/stdc++.h>
using namespace std;
long long mx[800][800] = {};
struct path {
  long long a, b, w;
  path(long long a, long long b, long long w) : a(a), b(b), w(w){};
};
vector<path> paths;
bool cmp(path &a, path &b) { return a.w < b.w; }
signed main() {
  vector<long long> coords, data;
  long long n, m, k;
  cin >> n >> m >> k;
  for (long long i = 0; i < m; i++) {
    long long a, b, w;
    cin >> a >> b >> w;
    paths.emplace_back(a, b, w);
  }
  sort(paths.begin(), paths.end(), cmp);
  vector<long long> tmp;
  for (long long i = 0; i < min(m, k); i++) {
    tmp.push_back(paths[i].a);
    tmp.push_back(paths[i].b);
  }
  sort(tmp.begin(), tmp.end());
  coords.push_back(tmp[0]);
  for (long long i = 1; i < tmp.size(); i++) {
    if (tmp[i] != tmp[i - 1]) coords.push_back(tmp[i]);
  }
  long long sz = coords.size();
  for (long long i = 0; i < sz; i++) {
    for (long long j = 0; j < sz; j++) mx[i][j] = (i == j ? 0 : 4e15 * 1ll);
  }
  for (long long i = 0; i < min(m, k); i++) {
    long long a, b;
    a = lower_bound(coords.begin(), coords.end(), paths[i].a) - coords.begin();
    b = lower_bound(coords.begin(), coords.end(), paths[i].b) - coords.begin();
    mx[a][b] = mx[b][a] = paths[i].w;
  }
  for (long long k = 0; k < sz; k++) {
    for (long long i = 0; i < sz; i++) {
      for (long long j = 0; j < sz; j++) {
        if (mx[i][k] + mx[k][j] < mx[i][j]) mx[i][j] = mx[i][k] + mx[k][j];
      }
    }
  }
  for (long long i = 0; i < sz; i++) {
    for (long long j = i + 1; j < sz; j++) {
      data.push_back(mx[i][j]);
    }
  }
  sort(data.begin(), data.end());
  cout << data[k - 1];
}
