N,M,K = map(int,input().split())
G = [[] for _ in range(N+1)]
_min = 10 ** 6
inf = 10 ** 6
for _ in range(M):
    a,b,c = map(int,input().split())
    G[a].append(b)
    G[b].append(a)
    if c < _min:
        _min = c
from collections import deque
q = deque()
q.append(1)
dist = [inf] * (N+1)
dist[1] = 0
while q:
    now = q.popleft()
    for v in G[now]:
        if dist[v] == inf:
            dist[v] = dist[now] + 1
            q.append(v)
if dist[-1] >= K:
    print(_min)
else:
    print(0)