## https://yukicoder.me/problems/no/1607

from collections import deque

MAX_INT = 10 ** 18

def solve(N, edges, K, value):
    next_nodes = [[] for _ in range(N)]
    for u, v, c in edges:
        if c > value:
            next_nodes[u].append((v, 1))
            next_nodes[v].append((u, 1))
        else:
            next_nodes[u].append((v, 0))
            next_nodes[v].append((u, 0))
    
    # 01BFSで問題を解く
    dists = [MAX_INT ] * N
    dists[0] = 0
    queue = deque()
    queue.append(0)
    while len(queue) > 0:
        v = queue.popleft()
        for w, cost in next_nodes[v]:
            if cost == 1:
                if dists[w] > dists[v] + 1:
                    dists[w] = dists[v] + 1
                    queue.append(w)
            elif cost == 0:
                if dists[w] > dists[v]:
                    dists[w] = dists[v]
                    queue.appendleft(w)
    return dists[N - 1] < K


def main():
    N, M, K = map(int, input().split())
    edges = []
    max_c = 0
    for _ in range(M):
        u, v, c = map(int, input().split())
        edges.append((u - 1, v - 1, c))
        max_c = max(c, max_c)
    
    low = 0
    high = max_c

    while high - low > 1:
        mid = (high + low) // 2
        if solve(N, edges, K, mid):
            high = mid
        else:
            low = mid
    if solve(N, edges, K, low):
        print(low)
    else:
        print(high)





                


if __name__ == "__main__":
    main()