#![allow(non_snake_case)]
#![allow(unused_imports)]
#![allow(unused_macros)]
#![allow(clippy::needless_range_loop)]
#![allow(clippy::comparison_chain)]
#![allow(clippy::nonminimal_bool)]
#![allow(clippy::neg_multiply)]
#![allow(dead_code)]
// use itertools::Itertools;
use std::cmp::Reverse;
use std::collections::{BTreeMap, BTreeSet, BinaryHeap, VecDeque};
// use superslice::Ext;
// use bitset_fixed::BitSet;

use proconio::{
    input,
    marker::{Chars, Usize1},
};

#[derive(Default)]
struct Solver {}
impl Solver {
    // #[fastout]
    fn solve(&mut self) {
        input! {
            N: usize,
            M: usize,
            X: usize,
            UVCT: [(Usize1, Usize1, usize, usize); M]
        }

        let mut G = vec![vec![]; N];
        for &(u, v, c, t) in UVCT.iter() {
            G[u].push((v, c, t));
            G[v].push((u, c, t));
        }

        let INF = 1_usize << 60;
        let mut dist = vec![INF; N];
        dist[0] = 0;
        let mut Q = BinaryHeap::new();
        Q.push((Reverse(0), 0, 0));
        while let Some((Reverse(d), pos, money)) = Q.pop() {
            if dist[pos] != d {
                continue;
            }
            for &(nxt, c, t) in &G[pos] {
                let tt = if c <= money {
                    0
                } else {
                    (c - money + X - 1) / X
                };
                let dd = t + tt;
                let next_money = tt * X + money - c;
                if dist[pos] + dd < dist[nxt] {
                    dist[nxt] = dist[pos] + dd;
                    Q.push((Reverse(dist[nxt]), nxt, next_money));
                }
            }
        }
        let ans = dist[N - 1];
        if ans == INF {
            println!("-1");
        } else {
            println!("{}", ans);
        }
    }
}

fn main() {
    std::thread::Builder::new()
        .stack_size(128 * 1024 * 1024)
        .spawn(|| Solver::default().solve())
        .unwrap()
        .join()
        .unwrap();
}