#include <bits/stdc++.h>
using namespace std;
using ll = long long;

struct Graph {
    struct Vertex { int n, d, c; };
    struct Edge { int i, n; };
    Graph(int n) : v(n, { -1, -1, 1 << 30 }), q(n), n(n), m(0) {}
    void add_edge(int i, int j) {
        e.push_back({ j, v[i].n });
        v[i].n = m;
        m++;
    }
    void bfs(int i0) {
        for (int i = 0; i < n; i++) {
            v[i].d = -1;
        }
        v[i0].d = 0;

        int j0 = 0, j1 = 0;
        q[j1++] = i0;

        while (j0 < j1) {
            int i = q[j0++];
            for (int j = v[i].n; j >= 0; j = e[j].n) {
                Edge &o = e[j];
                if (v[o.i].d >= 0) continue;

                v[o.i].d = v[i].d + 1;
                q[j1++] = o.i;
            }
        }
    }
    vector<Vertex> v;
    vector<Edge> e;
    vector<int> q;
    int n, m;
};

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n, m, k;
    cin >> n >> m >> k;

    Graph g(n);
    for (int i = 0; i < m; i++) {
        int u, v, c;
        cin >> u >> v >> c;
        u--; v--;

        g.add_edge(u, v);
        g.add_edge(v, u);
        g.v[u].c = min(g.v[u].c, c);
        g.v[v].c = min(g.v[v].c, c);
    }
    g.v[0].c = 0;

    g.bfs(n - 1);
    int r = 1 << 30;
    for (int i = 0; i < n; i++) {
        if (g.v[i].d < k) {
            r = min(r, g.v[i].c);
        }
    }
    cout << r << endl;

    return 0;
}