#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template<class T> using oset =
tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define ll long long
#define ld long double
#define ar array
#define vi vector<int>
#define vii vector<vector<int>>
#define pii pair<int, int>
#define pb push_back
#define all(x) x.begin(), x.end()
#define f first
#define s second
#define endl "\n"
const int MOD = 1e9+7;
const int inf = 1e9;
const ll linf = 1e18;
const int d4i[4]={-1, 0, 1, 0}, d4j[4]={0, 1, 0, -1};
const int d8i[8]={-1, -1, 0, 1, 1, 1, 0, -1}, d8j[8]={0, 1, 1, 1, 0, -1, -1, -1};
// -------------------------------------------------- Main Code --------------------------------------------------
void sol() {
int n, m; cin >> n >> m;
map<int, vector<array<int, 3>>> g[n];
map<int, int> vis[n], pref[n];
for (int i = 0; i < m; i++) {
int a, b, c, d; cin >> a >> b >> c >> d; --a; --b;
g[a][c].pb({b, c, d});
g[b][c].pb({a, c, d});
pref[a][c] += d;
pref[b][c] += d;
}
priority_queue<array<int, 3>, vector<array<int, 3>>, greater<array<int, 3>>> q;
q.push({0, 0, 0}); // dis, src, colour
while (!q.empty()) {
auto temp = q.top(); q.pop();
int dist = temp[0], src = temp[1], col = temp[2];
if (vis[src][col]) continue;
vis[src][col] = true;
if (src == n-1 && !col) {
cout << dist << endl;
return;
}
if (col) {
for (auto ch : g[src][col]) {
int child = ch[0], chCol = ch[1], chp = ch[2];
q.push({pref[src][chCol] - chp + dist, child, 0});
}
}
else {
for (auto chi : g[src]) {
for (auto ch : chi.s) {
int child = ch[0], chCol = ch[1], chp = ch[2];
q.push({min(pref[src][chCol] - chp + dist, chp + dist), child, 0});
q.push({dist, child, chCol});
}
}
}
}
cout << -1 << endl;
}
int main () {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int t = 1;
// cin >> t;
while (t--) {
sol();
}
return 0;
}
