#include <bits/stdc++.h> #define d1(x) cout << #x << " : " << x << endl << flush #define d2(x, y) cout << #x << " : " << x << " " << #y << " : " << y << endl << flush #define d3(x, y, z) cout << #x << " : " << x << " " << #y << " : " << y << " " << #z << " : " << z << endl << flush #define d4(x, y, z, a) cout << #x << " : " << x << " " << #y << " : " << y << " " << #z << " : " << z << " "<< #a << " : " << a << endl << flush #define arr(x) array <ll, x> #define ld long double #define ll long long #define int long long #define pb push_back #define endl '\n' #define lc v << 1 #define rc v << 1 | 1 using namespace std; const int INF = 1e14 + (35 / 10); // 35 ---> 36 const int MAXN = 2e5 + (35 / 10); // 35 ---> 36 vector <arr(3)> adj[MAXN]; map <arr(2), int> dp; map <arr(2), int> mp; signed main(){ ios_base::sync_with_stdio(0); cin.tie(0); int n, m; cin >> n >> m; for(int i = 1; i < n; i++) dp[{i, 0}] = INF; for(int i = 1; i <= m; i++){ int u, v, c, p; cin >> u >> v >> c >> p; u--; v--; adj[u].pb({v, c, p}); adj[v].pb({u, c, p}); mp[{u, c}] += p; mp[{v, c}] += p; dp[{u, c}] = dp[{v, c}] = INF; } dp[{0, 0}] = 0; set <arr(6)> s; s.insert({0, 0, 0, -1, -INF, 0}); while(!s.empty()){ auto [w, u, cool, eli, pp, E] = *s.begin(); s.erase(s.begin()); // d4(w, u, cool, C[id]); for(int i = 0; i < adj[u].size(); i++){ auto [v, c, p] = adj[u][i]; if(dp[{v, 0}] > w + p){ dp[{v, 0}] = w + p; s.insert({dp[{v, 0}], v, 0, c, p, u}); } if(cool != c){ int cost = mp[{u, c}] - p; if(cool == 0 && eli == c && E != v) cost -= pp; // d1(cost); if(dp[{v, c}] > w + cost){ dp[{v, c}] = w + cost; s.insert({dp[{v, c}], v, c, -1, -1, u}); } } // d3(i, u, v); // d1(2); } // d3(w, u, eli); // cout << endl; } // cout << mp[{1, 3}] << " " << mp[{3, 3}] << endl; int ans = INF; for(auto [v, c, p] : adj[n - 1]) ans = min(ans, dp[{n - 1, c}]); if(ans == INF) ans = -1; cout << ans << endl; } // Ey To Bahane! :_))) // -------------<3------------- // /* Magasan dor shirini: 1. MAXN 2. Input style 3. index or value? Masale In Ast! 4. MOD */