#include <iostream>
#include <vector>
#include <queue>
#include <algorithm>
#include <tuple>
using namespace std;
using ll = long long;

bool f(const vector<vector<tuple<ll, ll, ll>>>& G, ll N, ll X, ll m) {
    priority_queue<tuple<ll, ll>> S;
    vector<bool> fixed(N, false);
    vector<ll> D(N, X + 1);
    D[0] = 0;
    S.push(make_tuple(0, 0));
    while (!S.empty()) {
      auto [c, i] = S.top();
      S.pop();
      if (i == N - 1) {
        break;
      }
      if (fixed[i]) {
        continue;
      }
      fixed[i] = true;
      for (auto& [b, j, a] : G[i]) {
        if (m > b) {
          continue;
        }
        if (D[j] <= c + a) {
          continue;
        }
        if (c + a > X) {
          continue;
        }
        D[j] = c + a;
        S.push(make_tuple(c + a, j));
      }
    }
    return D[N - 1] <= X;
}

int main() {
    ll N, M, X;
    cin >> N >> M >> X;
    
    ll u, v, a, b;
    vector<vector<tuple<ll, ll, ll>>> G(N);
    for (ll i; i < M; ++i) {
      cin >> u >> v >> a >> b;
      --u;
      --v;
      G[u].push_back(make_tuple(b, v, a));
      G[v].push_back(make_tuple(b, u, a));
    }
    
    ll l = -1;
    ll r = 1e9 + 10;
    while (r - l > 1) {
        ll m = (l + r) / 2;
        if (f(G, N, X, m)) {
            l = m;
        } else {
            r = m;
        }
    }

    cout << l << endl;
    
    return 0;
}