#include <bits/stdc++.h>
using namespace std;
const long long maxn = 810;
const long long N = 2e5 + 10;
const long long M = 2e5 + 10;
const long long inf = 0x3f3f3f3f3f3f3f3f;
struct eg {
  long long u, v, w;
  bool operator<(const eg& _) const { return w < _.w; }
} a[M];
long long n, m, k, dp[maxn][maxn], dis[N], cnt, tot;
long long b[N];
signed main() {
  memset(dp, 0x3f, sizeof dp);
  cin >> n >> m >> k;
  for (long long i = 1; i <= m; i++) cin >> a[i].u >> a[i].v >> a[i].w;
  sort(a + 1, a + m + 1);
  for (long long i = 1; i <= min(k, m); i++)
    b[++cnt] = a[i].u, b[++cnt] = a[i].v;
  sort(b + 1, b + cnt + 1);
  n = unique(b + 1, b + cnt + 1) - b - 1;
  for (long long i = 1; i <= min(k, m); i++) {
    long long f = lower_bound(b + 1, b + n + 1, a[i].u) - b,
              t = lower_bound(b + 1, b + n + 1, a[i].v) - b;
    dp[f][t] = dp[t][f] = a[i].w;
  }
  for (long long kk = 1; kk <= n; ++kk)
    for (long long i = 1; i <= n; ++i)
      for (long long j = 1; j <= n; ++j)
        if (dp[i][kk] + dp[kk][j] < dp[i][j]) dp[i][j] = dp[i][kk] + dp[kk][j];
  for (long long i = 1; i <= n; ++i)
    for (long long j = i + 1; j <= n; ++j)
      if (dp[i][j] != inf) dis[++tot] = dp[i][j];
  sort(dis + 1, dis + tot + 1);
  cout << dis[k] << endl;
  return 0;
}
