#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i,a,b) for(ll i=(ll)(a);i<(ll)(b);i++)
#define rrep(i,a,b) for(ll i=(ll)(a-1);i>=(ll)(b);i--)
#define MOD 998244353
#define INF 1e16
template <typename T> bool chmax(T& a,T b){if(a<b){a=b;return 1;}return 0;}
template <typename T> bool chmin(T& a,T b){if(a>b){a=b;return 1;}return 0;}
ll comb(ll x,ll y){
    ll ans=1;
    rep(i,0,y) ans*=(x-i);
    rep(i,0,y) ans/=(i+1);
    return ans;
}
ll rui(ll x){
    if(x==0) return 1;
    return 2*rui(x-1);
}
ll fac(ll x){
    if(x==0) return 1;
    return x*fac(x-1);
}
ll pow(ll x,ll n){
    ll ans=1;
    while(n>0){
        if(n&1) ans*=x;
        x*=x;
        n>>=1;
    }
    return ans;
}

ll n,m,x;
vector<vector<pair<ll,pair<ll,ll>>>> g;
bool dijkstra(vector<vector<pair<ll,pair<ll,ll>>>>& g,ll h){
    vector<ll> d(n,1e18);
    priority_queue<pair<ll,pair<ll,ll>>,vector<pair<ll,pair<ll,ll>>>,greater<pair<ll,pair<ll,ll>>>> pq;
    pq.push({0,{0,1e18}});
    while(!pq.empty()){
        ll x=pq.top().first,y=pq.top().second.first,z=pq.top().second.second;
        if(d[y]>x){
            d[y]=x;
            for(auto&& [p,q]:g[y]){
                if(q.second<h) continue;
                pq.push({q.first+x,{p,q.second}});
            }
        }
        pq.pop();
    }
    return d[n-1]<=x;
}

int main(){
    cin >> n >> m >> x;
    vector<ll> u(m),v(m),a(m),b(m);
    g.resize(n);
    rep(i,0,m){
        cin >> u[i] >> v[i] >> a[i] >> b[i];
        u[i]--,v[i]--;
        g[u[i]].push_back({v[i],{a[i],b[i]}});
        g[v[i]].push_back({u[i],{a[i],b[i]}});
    }
    ll p=-1,q=1e9;
    while(q-p>1){
        ll r=(p+q)/2;
        if(dijkstra(g,r)) p=r;
        else q=r;
    }
    cout << p << endl;
}