use std::collections::VecDeque;

const INF: usize = 1usize << 60;

fn process(paths: &Vec<Vec<(usize, usize)>>, result: &mut usize, checked: &mut Vec<bool>, deque: &mut VecDeque<usize>) {
    let limit = deque.len();
    for _ in 0..limit {
        let u = deque.pop_front().unwrap();
        for &(v, c) in paths[u].iter() {
            if checked[v] { continue; }
            *result = (*result).min(c);
            checked[v] = true;
            deque.push_back(v);
        }
    }
}

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 checked = vec![false; n];
    checked[n-1] = true;
    let mut deque = VecDeque::new();
    deque.push_back(n-1);
    let mut result = INF;
    for _ in 0..k-1 {
        process(&paths, &mut result, &mut checked, &mut deque);
    }
    if checked[0] {
        println!("0");
        return;
    }
    process(&paths, &mut result, &mut checked, &mut deque);
    println!("{}", result);
}