#include <bits/stdc++.h>
inline long long read() {
  long long f = 1, x = 0;
  char ch = getchar();
  while (!(ch >= '0' && ch <= '9')) {
    if (ch == '-') f *= -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = x * 10 + ch - '0';
    ch = getchar();
  }
  return f * x;
}
struct Edge {
  int x, y, c;
} a[200000 + 1];
bool cmp(Edge x, Edge y) { return x.c < y.c; }
std::map<int, int> map;
int n, m, k, len;
long long d[2 * 400 + 1][2 * 400 + 1], ans[4 * 400 * 400 + 1];
int main() {
  n = read(), m = read(), k = read();
  for (int i = 1; i <= m; i++)
    a[i].x = read(), a[i].y = read(), a[i].c = read();
  std::sort(a + 1, a + m + 1, cmp);
  len = 0;
  memset(d, 63, sizeof(d));
  for (int i = 1; i <= k; i++) {
    if (map[a[i].x] == 0) map[a[i].x] = ++len;
    if (map[a[i].y] == 0) map[a[i].y] = ++len;
    a[i].x = map[a[i].x], a[i].y = map[a[i].y];
    d[a[i].x][a[i].y] = d[a[i].y][a[i].x] = a[i].c;
  }
  for (int p = 1; p <= len; p++) {
    for (int i = 1; i <= len; i++)
      if (i != p) {
        for (int j = 1; j <= len; j++)
          if (i != p && j != p) {
            d[i][j] = std::min(d[i][j], d[i][p] + d[p][j]);
          }
      }
  }
  ans[0] = 0;
  for (int i = 1; i <= len; i++)
    for (int j = i + 1; j <= len; j++) ans[++ans[0]] = d[i][j];
  std::sort(ans + 1, ans + ans[0] + 1);
  printf("%lld\n", ans[k]);
}
