#include <stdio.h>

typedef struct List {
	struct List *next;
	int v, cost;
} list;

int main()
{
	int i, N, M, K, u, w, c;
	list *adj[200001] = {}, e[400001], *p;
	scanf("%d %d %d", &N, &M, &K);
	for (i = 0; i < M; i++) {
		scanf("%d %d %d", &u, &w, &c);
		e[i*2].v = w;
		e[i*2+1].v = u;
		e[i*2].cost = c;
		e[i*2+1].cost = c;
		e[i*2].next = adj[u];
		e[i*2+1].next = adj[w];
		adj[u] = &(e[i*2]);
		adj[w] = &(e[i*2+1]);
	}
	
	const int sup = 1 << 20;
	int l = 0, r = 200000, m, dist[200001], q[400001][2], head, tail;
	while (l < r) {
		m = (l + r) / 2;
		for (u = 2, dist[1] = 0; u <= N; u++) dist[u] = sup;
		head = N;
		tail = N;
		q[tail][0] = 1;
		q[tail++][1] = 0;
		for (; head < tail; head++) {
			u = q[head][0];
			if (q[head][1] != dist[u]) continue;
			for (p = adj[u]; p != NULL; p = p->next) {
				w = p->v;
				if (p->cost <= m && dist[w] > dist[u]) {
					dist[w] = dist[u];
					q[head][0] = w;
					q[head--][1] = dist[w];
				} else if (p->cost > m && dist[w] > dist[u] + 1) {
					dist[w] = dist[u] + 1;
					q[tail][0] = w;
					q[tail++][1] = dist[w];
				}
			}
		}
		if (dist[N] >= K) l = m + 1;
		else r = m;
	}
	printf("%d\n", l);
	fflush(stdout);
	return 0;
}