#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 7;
struct edge {
  int u, v;
  long long c;
  bool operator<(const edge &tmp) const { return c < tmp.c; }
} A[N];
bool vis[N];
int B[808], C[808];
long long dis[808][808], D[808 * 404];
int main() {
  int n, m, k, maxx = 0;
  scanf("%d %d %d", &n, &m, &k);
  for (int i = 0; i < m; i++) {
    int u, v, c;
    scanf("%d %d %I64d", &A[i].u, &A[i].v, &A[i].c);
  }
  int b = min(k, m), c = 0;
  sort(A, A + m);
  for (int i = 0; i < b; i++) {
    if (!vis[A[i].u]) {
      B[++c] = A[i].u;
      vis[A[i].u] = 1;
    }
    if (!vis[A[i].v]) {
      B[++c] = A[i].v;
      vis[A[i].v] = 1;
    }
  }
  sort(B + 1, B + 1 + c);
  memset(dis, 0x3f3f, sizeof(dis));
  for (int i = 0; i < b; i++) {
    int u = lower_bound(B + 1, B + 1 + c, A[i].u) - B;
    int v = lower_bound(B + 1, B + 1 + c, A[i].v) - B;
    dis[u][v] = dis[v][u] = A[i].c;
  }
  for (int i = 1; i <= c; i++) {
    for (int j = 1; j <= c; j++) {
      for (int k = 1; k <= c; k++) {
        dis[j][k] = min(dis[j][k], dis[j][i] + dis[i][k]);
      }
    }
  }
  int d = 0;
  for (int i = 1; i < c; i++) {
    for (int j = i + 1; j <= c; j++) {
      D[++d] = dis[i][j];
    }
  }
  sort(D + 1, D + 1 + d);
  printf("%I64d\n", D[k]);
}
