#include //#include //using namespace atcoder; #pragma GCC target ("avx2") #pragma GCC optimization ("O3") #pragma GCC optimization ("unroll-loops") using namespace std; typedef vector vi; typedef vector VI; typedef vector VVI; typedef vector VS; typedef pair PII; typedef pair pii; typedef pair PLL; typedef pair TIII; typedef long long LL; typedef long long ll; typedef unsigned long long ULL; typedef long double ld; typedef vector VLL; typedef vector VVLL; #define FOR(i, s, n) for (int i = s; i < (int)n; ++i) #define REP(i, n) FOR(i, 0, n) #define rep(i, a, b) for (int i = a; i < (b); ++i) #define trav(a, x) for (auto &a : x) #define all(x) x.begin(), x.end() #define MOD 1000000007 template inline bool chmax(T1 &a, T2 b) {if (a < b) {a = b; return true;} return false;} template inline bool chmin(T1 &a, T2 b) {if (a > b) {a = b; return true;} return false;} const double EPS = 1e-9, PI = acos(-1); const double pi = 3.141592653589793238462643383279; //ここから編集 typedef string::const_iterator State; template< int mod > struct ModInt { int x; ModInt() : x(0) {} ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {} ModInt &operator+=(const ModInt &p) { if((x += p.x) >= mod) x -= mod; return *this; } ModInt &operator-=(const ModInt &p) { if((x += mod - p.x) >= mod) x -= mod; return *this; } ModInt &operator*=(const ModInt &p) { x = (int) (1LL * x * p.x % mod); return *this; } ModInt &operator/=(const ModInt &p) { *this *= p.inverse(); return *this; } ModInt operator-() const { return ModInt(-x); } ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; } ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; } ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; } ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; } bool operator==(const ModInt &p) const { return x == p.x; } bool operator!=(const ModInt &p) const { return x != p.x; } ModInt inverse() const { int a = x, b = mod, u = 1, v = 0, t; while(b > 0) { t = a / b; swap(a -= t * b, b); swap(u -= t * v, v); } return ModInt(u); } ModInt pow(int64_t n) const { ModInt ret(1), mul(x); while(n > 0) { if(n & 1) ret *= mul; mul *= mul; n >>= 1; } return ret; } friend ostream &operator<<(ostream &os, const ModInt &p) { return os << p.x; } friend istream &operator>>(istream &is, ModInt &a) { int64_t t; is >> t; a = ModInt< mod >(t); return (is); } static int get_mod() { return mod; } }; using modint = ModInt< 998244353 >; template< typename T > struct Combination { vector< T > _fact, _rfact, _inv; Combination(int sz) : _fact(sz + 1), _rfact(sz + 1), _inv(sz + 1) { _fact[0] = _rfact[sz] = _inv[0] = 1; for(int i = 1; i <= sz; i++) _fact[i] = _fact[i - 1] * i; _rfact[sz] /= _fact[sz]; for(int i = sz - 1; i >= 0; i--) _rfact[i] = _rfact[i + 1] * (i + 1); for(int i = 1; i <= sz; i++) _inv[i] = _rfact[i] * _fact[i - 1]; } inline T fact(int k) const { return _fact[k]; } inline T rfact(int k) const { return _rfact[k]; } inline T inv(int k) const { return _inv[k]; } T P(int n, int r) const { if(r < 0 || n < r) return 0; return fact(n) * rfact(n - r); } T C(int p, int q) const { if(q < 0 || p < q) return 0; return fact(p) * rfact(q) * rfact(p - q); } T H(int n, int r) const { if(n < 0 || r < 0) return (0); return r == 0 ? 1 : C(n + r - 1, r); } }; ll GCD(ll a, ll b){ return (b==0)?a:GCD(b, a%b); } ll LCM(ll a, ll b){ return a/GCD(a, b) * b; } 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(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(10); int n, m; cin >> n >> m; int s = 0, t = n-1; PrimalDual flow(n); REP(i,m){ int u, v, c, d; cin >> u >> v >> c >> d; u--; v--; flow.add_edge(u, v, 1, c); flow.add_edge(v, u, 1, c); flow.add_edge(u, v, 1, d); flow.add_edge(v, u, 1, d); } cout << flow.min_cost_flow(s, t, 2) << endl; return 0; }