use std::collections::VecDeque;


const INF: usize = 1usize << 60;

fn main() {
    let mut nmk = String::new();
    std::io::stdin().read_line(&mut nmk).ok();
    let nmk: Vec<usize> = nmk.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
    let n = nmk[0];
    let m = nmk[1];
    let k = nmk[2];
    let mut paths = vec![vec![]; n];
    for _ in 0..m {
        let mut temp = String::new();
        std::io::stdin().read_line(&mut temp).ok();
        let temp: Vec<usize> = temp.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();
        let u = temp[0]-1;
        let v = temp[1]-1;
        let c = temp[2];
        paths[u].push((v, c));
        paths[v].push((u, c));
    }

    let mut lower = 0usize;
    let mut upper = INF;
    while upper > lower {
        let middle = (upper + lower) / 2;
        let mut dists = vec![INF; n];
        dists[0] = 0;
        let mut deque = VecDeque::new();
        deque.push_back(0);
        while let Some(u) = deque.pop_front() {
            for &(v, c) in paths[u].iter() {
                let ncost = dists[u] + if c > middle { 1 } else { 0 };
                if ncost >= dists[v] { continue; }
                dists[v] = ncost;
                if c > middle {
                    deque.push_back(v);
                } else {
                    deque.push_front(v);
                }
            }
        }
        if dists[n-1] < k {
            upper = middle;
        } else {
            lower = middle + 1;
        }
    }
    println!("{}", upper);
}