#pragma GCC target("avx2") #pragma GCC optimize("Ofast") #pragma GCC optimize("unroll-loops") #include using namespace std; #define DEBUG #ifdef DEBUG template ostream &operator<<(ostream &os, const pair &p) { os << '(' << p.first << ',' << p.second << ')'; return os; } template ostream &operator<<(ostream &os, const vector &v) { os << '{'; for(int i = 0; i < (int)v.size(); i++) { if(i) { os << ','; } os << v[i]; } os << '}'; return os; } void debugg() { cerr << endl; } template void debugg(const T &x, const Args &... args) { cerr << " " << x; debugg(args...); } #define debug(...) \ cerr << __LINE__ << " [" << #__VA_ARGS__ << "]: ", debugg(__VA_ARGS__) #define dump(x) cerr << __LINE__ << " " << #x << " = " << (x) << endl #else #define debug(...) (void(0)) #define dump(x) (void(0)) #endif using namespace std; typedef long long ll; typedef vector vl; typedef vector vvl; typedef vector vc; typedef vector vs; typedef vector vb; typedef vector vd; typedef pair P; typedef pair pii; typedef vector

vpl; typedef tuple tapu; #define rep(i,n) for(int i=0; i<(n); i++) #define REP(i,a,b) for(int i=(a); i<(b); i++) #define all(x) (x).begin(), (x).end() #define rall(x) (x).rbegin(), (x).rend() const int inf = 1<<30; const ll linf = 1LL<<62; const int MAX = 510000; int dy[8] = {0,-1,0,1,1,-1,-1,1}; int dx[8] = {-1,0,1,0,1,-1,1,-1}; const double pi = acos(-1); const double eps = 1e-7; template inline bool chmin(T1 &a,T2 b){ if(a>b){ a = b; return true; } else return false; } template inline bool chmax(T1 &a,T2 b){ if(a inline void print(T &a){ int sz = a.size(); for(auto itr = a.begin(); itr != a.end(); itr++){ cout << *itr; sz--; if(sz) cout << " "; } cout << "\n"; } template inline void print2(T1 a, T2 b){ cout << a << " " << b << "\n"; } template inline void print3(T1 a, T2 b, T3 c){ cout << a << " " << b << " " << c << "\n"; } void mark() {cout << "#" << "\n";} ll pcount(ll x) {return __builtin_popcountll(x);} //const int mod = 1e9 + 7; const int mod = 998244353; template< typename flow_t, typename cost_t > struct PrimalDual { const cost_t INF; struct edge { int to; flow_t cap; cost_t cost; int rev; bool isrev; }; vector< vector< edge > > graph; vector< cost_t > potential, min_cost; vector< int > prevv, preve; PrimalDual(int V) : graph(V), INF(numeric_limits< cost_t >::max()) {} void add_edge(int from, int to, flow_t cap, cost_t cost) { graph[from].emplace_back((edge) {to, cap, cost, (int) graph[to].size(), false}); graph[to].emplace_back((edge) {from, 0, -cost, (int) graph[from].size() - 1, true}); } cost_t min_cost_flow(int s, int t, flow_t f) { int V = (int) graph.size(); cost_t ret = 0; using Pi = pair< cost_t, int >; priority_queue< Pi, vector< Pi >, greater< Pi > > que; potential.assign(V, 0); preve.assign(V, -1); prevv.assign(V, -1); while(f > 0) { min_cost.assign(V, INF); que.emplace(0, s); min_cost[s] = 0; while(!que.empty()) { Pi p = que.top(); que.pop(); if(min_cost[p.second] < p.first) continue; for(int i = 0; i < graph[p.second].size(); i++) { edge &e = graph[p.second][i]; cost_t nextCost = min_cost[p.second] + e.cost + potential[p.second] - potential[e.to]; if(e.cap > 0 && min_cost[e.to] > nextCost) { min_cost[e.to] = nextCost; prevv[e.to] = p.second, preve[e.to] = i; que.emplace(min_cost[e.to], e.to); } } } if(min_cost[t] == INF) return -1; for(int v = 0; v < V; v++) potential[v] += min_cost[v]; flow_t addflow = f; for(int v = t; v != s; v = prevv[v]) { addflow = min(addflow, graph[prevv[v]][preve[v]].cap); } f -= addflow; ret += addflow * potential[t]; for(int v = t; v != s; v = prevv[v]) { edge &e = graph[prevv[v]][preve[v]]; e.cap -= addflow; graph[v][e.rev].cap += addflow; } } return ret; } void output() { for(int i = 0; i < graph.size(); i++) { for(auto &e : graph[i]) { if(e.isrev) continue; auto &rev_e = graph[e.to][e.rev]; cout << i << "->" << e.to << " (flow: " << rev_e.cap << "/" << rev_e.cap + e.cap << ")" << endl; } } } }; int main(){ ll n,m; cin >> n >> m; PrimalDual G(n); rep(i,m){ ll u,v,c,d; cin >> u >> v >> c >> d; u--; v--; G.add_edge(u,v,1,c); G.add_edge(u,v,1,d); G.add_edge(v,u,1,c); G.add_edge(v,u,1,d); } ll ans = G.min_cost_flow(0,n-1,2); cout << ans << "\n"; }