from sys import stdin
from collections import deque

n, m, k, *indata = map(int, stdin.read().split())
offset = 0
g = [[] for i in range(n+1)]
for i in range(m):
    s, t, d  = indata[offset + 3*i],indata[offset + 3*i+1],indata[offset + 3*i+2]
    g[s].append((t,d))
    g[t].append((s,d))

que = deque()
que.append(1)
dist = [0 for i in range(n+1)]
check = [0 for i in range(n+1)]
check[1] = 1
while que:
    now = que.popleft()
    if now == n:
        break
    for i, c in g[now]:
        if check[i] == 0:
            check[i] = 1
            dist[i] = dist[now] + 1
            que.append(i)

if dist[n] <= k-1:
    print("{}".format(0))
    exit()

left = 0
right = 2 * (10**5) + 1

while right - left >= 2:
    mid = (right + left) // 2
    que = deque()
    que.append((1,0))
    dist = [0 for i in range(n+1)]
    check = [0 for i in range(n+1)]
    while que:
        now, d = que.popleft()
        if check[now] == 0:
            check[now] = 1
            dist[now] = d
            if now == n:
                break
            for i, c in g[now]:
                if check[i] == 0:
                    if c > mid:
                        que.append((i,d+1))
                    else:
                        que.appendleft((i,d))
    if dist[n] <= k-1:
        right = mid
    else:
        left = mid

print("{}".format(right))