#include <bits/stdc++.h>
using namespace std;
inline int read() {
  int x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = (x << 3) + (x << 1) + ch - '0';
    ch = getchar();
  }
  return x * f;
}
const int MN = 2e5 + 5;
struct edge {
  int a, b, w;
} e[MN];
int N, M, K, nm[MN], tot;
bool cmp(const edge &x, const edge &y) { return x.w < y.w; }
priority_queue<long long> q;
void Add(long long x) {
  q.push(x);
  while (q.size() > K) q.pop();
}
long long d[900][900];
bool lt[900][900];
void fz(int x) {
  if (!nm[x]) nm[x] = ++tot;
}
void rw(long long &x, long long y) { x = min(x, y); }
int main() {
  register int i, j, k;
  N = read(), M = read(), K = read();
  for (i = 1; i <= M; ++i) e[i].a = read(), e[i].b = read(), e[i].w = read();
  std::sort(e + 1, e + M + 1, cmp);
  memset(d, 0x3f, sizeof d);
  for (i = 1; i <= M && i <= 400; ++i)
    fz(e[i].a), fz(e[i].b), rw(d[nm[e[i].a]][nm[e[i].b]], e[i].w),
        rw(d[nm[e[i].b]][nm[e[i].a]], e[i].w),
        lt[nm[e[i].a]][nm[e[i].b]] = true, lt[nm[e[i].b]][nm[e[i].a]] = true;
  for (k = 1; k <= tot; ++k)
    for (i = 1; i <= tot; ++i)
      for (j = 1; j <= tot; ++j)
        if (lt[i][k] && lt[k][j]) {
          lt[i][j] = lt[j][i] = true;
          rw(d[i][j], d[i][k] + d[k][j]);
        }
  for (i = 1; i <= tot; ++i)
    for (j = i + 1; j <= tot; ++j) Add(d[i][j]);
  printf("%lld\n", q.top());
  return 0;
}
