#include #define REP(i, n) for(int i = 0;i < n;i++) #define ll long long using namespace std; typedef pair P; typedef pair LP; const int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1}; const int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1}; const int INF = 1000000000; const ll LINF = 1000000000000000000;//1e18 const double PI = acos(-1.0); const double EPS = 1e-10; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; } /* ----------------------- DEBUG FUNCTION ---------------------------- */ #define DUMPOUT cerr void dump_function() { DUMPOUT << ' '; } void dump_function(bool a) { DUMPOUT << a; } void dump_function(int a) { DUMPOUT << a; } void dump_function(long long a) { DUMPOUT << a; } void dump_function(char a) { DUMPOUT << a; } void dump_function(string &a) { DUMPOUT << a; } void dump_function(double a) { DUMPOUT << a; } template void dump_function(const vector &); template void dump_function(const array &); template void dump_function(const pair &p); template void dump_function(const T (&)[size]); template void dump_function(const vector &a) { if(a.empty()) return; dump_function(a[0]); for(auto i = a.begin(); ++i != a.end();) { DUMPOUT << " "; dump_function(*i); } DUMPOUT << endl; } template void dump_function(const deque &a) { if(a.empty()) return; dump_function(a[0]); for(auto i = a.begin(); ++i != a.end();) { DUMPOUT << " "; dump_function(*i); } } template void dump_function(const array &a) { dump_function(a[0]); for(auto i = a.begin(); ++i != a.end();) { DUMPOUT << " "; dump_function(*i); } } template void dump_function(const pair &p) { DUMPOUT << '('; dump_function(p.first); DUMPOUT << ","; dump_function(p.second); DUMPOUT << ')'; } template void dump_function(set &x) { for(auto e : x) dump_function(e), DUMPOUT << " "; DUMPOUT << endl; } template void dump_function(multiset &x) { for(auto e : x) dump_function(e), DUMPOUT << " "; DUMPOUT << endl; } template void dump_function(const T (&a)[size]) { dump_function(a[0]); for(auto i = a; ++i != end(a);) { DUMPOUT << " "; dump_function(*i); } } template void dump_function(const T &a) { DUMPOUT << a; } int dump_out() { DUMPOUT << '\n'; return 0; } template int dump_out(const T &t) { dump_function(t); DUMPOUT << '\n'; return 0; } template int dump_out(const Head &head, const Tail &... tail) { dump_function(head); DUMPOUT << ' '; dump_out(tail...); return 0; } #ifdef DEBUG_ #define dump(x) \ DUMPOUT << #x << ": "; \ dump_function(x); \ DUMPOUT << endl; void dumps() {} template void dumps(const T &t) { dump_function(t); DUMPOUT << " "; } template void dumps(const Head &head, const Tail &... tail) { dump_function(head); DUMPOUT << ' '; dump_out(tail...); } #else #define dump(x) template void dumps(const T &...) {} #endif /* ----------------------- DEBUG FUNCTION ---------------------------- */ template struct Fp { long long val; constexpr Fp(long long v = 0) noexcept : val(v % MOD) { if (val < 0) val += MOD; } constexpr int getmod() const { return MOD; } constexpr Fp operator - () const noexcept { return val ? MOD - val : 0; } constexpr Fp operator + (const Fp& r) const noexcept { return Fp(*this) += r; } constexpr Fp operator - (const Fp& r) const noexcept { return Fp(*this) -= r; } constexpr Fp operator * (const Fp& r) const noexcept { return Fp(*this) *= r; } constexpr Fp operator / (const Fp& r) const noexcept { return Fp(*this) /= r; } constexpr Fp& operator += (const Fp& r) noexcept { val += r.val; if (val >= MOD) val -= MOD; return *this; } constexpr Fp& operator -= (const Fp& r) noexcept { val -= r.val; if (val < 0) val += MOD; return *this; } constexpr Fp& operator *= (const Fp& r) noexcept { val = val * r.val % MOD; return *this; } constexpr Fp& operator /= (const Fp& r) noexcept { long long a = r.val, b = MOD, u = 1, v = 0; while (b) { long long t = a / b; a -= t * b, swap(a, b); u -= t * v, swap(u, v); } val = val * u % MOD; if (val < 0) val += MOD; return *this; } constexpr bool operator == (const Fp& r) const noexcept { return this->val == r.val; } constexpr bool operator != (const Fp& r) const noexcept { return this->val != r.val; } friend constexpr istream& operator >> (istream& is, Fp& x) noexcept { is >> x.val; x.val %= MOD; if (x.val < 0) x.val += MOD; return is; } friend constexpr ostream& operator << (ostream& os, const Fp& x) noexcept { return os << x.val; } friend constexpr Fp modpow(const Fp& r, long long n) noexcept { if (n == 0) return 1; auto t = modpow(r, n / 2); t = t * t; if (n & 1) t = t * r; return t; } friend constexpr Fp modinv(const Fp& r) noexcept { long long a = r.val, b = MOD, u = 1, v = 0; while (b) { long long t = a / b; a -= t * b, swap(a, b); u -= t * v, swap(u, v); } return Fp(u); } }; template struct BiCoef { vector fact_, inv_, finv_; constexpr BiCoef() {} constexpr BiCoef(int n) noexcept : fact_(n, 1), inv_(n, 1), finv_(n, 1) { init(n); } constexpr void init(int n) noexcept { fact_.assign(n, 1), inv_.assign(n, 1), finv_.assign(n, 1); int MOD = fact_[0].getmod(); for(int i = 2; i < n; i++){ fact_[i] = fact_[i-1] * i; inv_[i] = -inv_[MOD%i] * (MOD/i); finv_[i] = finv_[i-1] * inv_[i]; } } constexpr T com(int n, int k) const noexcept { if (n < k || n < 0 || k < 0) return 0; return fact_[n] * finv_[k] * finv_[n-k]; } constexpr T fact(int n) const noexcept { if (n < 0) return 0; return fact_[n]; } constexpr T inv(int n) const noexcept { if (n < 0) return 0; return inv_[n]; } constexpr T finv(int n) const noexcept { if (n < 0) return 0; return finv_[n]; } constexpr T perm(int n, int k) const noexcept { if (n < k || n < 0 || k < 0) return 0; return fact_[n] * finv_[n-k]; } }; /* ----------------------------- MOD ----------------------------------- */ const int MOD = 1000000007; const int MOD2 = 998244353; using mint = Fp; BiCoef bc; // using vec = vector; // using mat = vector; /* ----------------------------- MOD ----------------------------------- */ /* ----------------------- AtCoder Library ---------------------------- */ // #include // using namespace atcoder; /* ----------------------- AtCoder Library ---------------------------- */ template struct mcf_graph { public: mcf_graph() {} mcf_graph(int n) : _n(n), g(n) {} int add_edge(int from, int to, Cap cap, Cost cost) { assert(0 <= from && from < _n); assert(0 <= to && to < _n); assert(0 <= cap); assert(0 <= cost); int m = int(pos.size()); pos.push_back({from, int(g[from].size())}); int from_id = int(g[from].size()); int to_id = int(g[to].size()); if (from == to) to_id++; g[from].push_back(_edge{to, to_id, cap, cost}); g[to].push_back(_edge{from, from_id, 0, -cost}); return m; } struct edge { int from, to; Cap cap, flow; Cost cost; }; edge get_edge(int i) { int m = int(pos.size()); assert(0 <= i && i < m); auto _e = g[pos[i].first][pos[i].second]; auto _re = g[_e.to][_e.rev]; return edge{ pos[i].first, _e.to, _e.cap + _re.cap, _re.cap, _e.cost, }; } std::vector edges() { int m = int(pos.size()); std::vector result(m); for (int i = 0; i < m; i++) { result[i] = get_edge(i); } return result; } std::pair flow(int s, int t) { return flow(s, t, std::numeric_limits::max()); } std::pair flow(int s, int t, Cap flow_limit) { return slope(s, t, flow_limit).back(); } std::vector> slope(int s, int t) { return slope(s, t, std::numeric_limits::max()); } std::vector> slope(int s, int t, Cap flow_limit) { assert(0 <= s && s < _n); assert(0 <= t && t < _n); assert(s != t); // variants (C = maxcost): // -(n-1)C <= dual[s] <= dual[i] <= dual[t] = 0 // reduced cost (= e.cost + dual[e.from] - dual[e.to]) >= 0 for all edge std::vector dual(_n, 0), dist(_n); std::vector pv(_n), pe(_n); std::vector vis(_n); struct Q { Cost key; int to; bool operator<(Q r) const { return key > r.key; } }; std::vector que; auto dual_ref = [&]() { std::fill(dist.begin(), dist.end(), std::numeric_limits::max()); std::fill(vis.begin(), vis.end(), false); que.clear(); dist[s] = 0; que.push_back(Q{0, s}); std::push_heap(que.begin(), que.end()); while (!que.empty()) { int v = que.front().to; std::pop_heap(que.begin(), que.end()); que.pop_back(); if (vis[v]) continue; vis[v] = true; if (v == t) break; // dist[v] = shortest(s, v) + dual[s] - dual[v] // dist[v] >= 0 (all reduced cost are positive) // dist[v] <= (n-1)C for (int i = 0; i < int(g[v].size()); i++) { auto e = g[v][i]; if (vis[e.to] || !e.cap) continue; // |-dual[e.to] + dual[v]| <= (n-1)C // cost <= C - -(n-1)C + 0 = nC Cost cost = e.cost - dual[e.to] + dual[v]; if (dist[e.to] - dist[v] > cost) { dist[e.to] = dist[v] + cost; pv[e.to] = v; pe[e.to] = i; que.push_back(Q{dist[e.to], e.to}); std::push_heap(que.begin(), que.end()); } } } if (!vis[t]) { return false; } for (int v = 0; v < _n; v++) { if (!vis[v]) continue; // dual[v] = dual[v] - dist[t] + dist[v] // = dual[v] - (shortest(s, t) + dual[s] - dual[t]) + (shortest(s, v) + dual[s] - dual[v]) // = - shortest(s, t) + dual[t] + shortest(s, v) // = shortest(s, v) - shortest(s, t) >= 0 - (n-1)C dual[v] -= dist[t] - dist[v]; } return true; }; Cap flow = 0; Cost cost = 0, prev_cost_per_flow = -1; std::vector> result; result.push_back({flow, cost}); while (flow < flow_limit) { if (!dual_ref()) break; Cap c = flow_limit - flow; for (int v = t; v != s; v = pv[v]) { c = std::min(c, g[pv[v]][pe[v]].cap); } for (int v = t; v != s; v = pv[v]) { auto& e = g[pv[v]][pe[v]]; e.cap -= c; g[v][e.rev].cap += c; } Cost d = -dual[s]; flow += c; cost += c * d; if (prev_cost_per_flow == d) { result.pop_back(); } result.push_back({flow, cost}); prev_cost_per_flow = d; } return result; } private: int _n; struct _edge { int to, rev; Cap cap; Cost cost; }; std::vector> pos; std::vector> g; }; void solve(){ int N, M; cin >> N >> M; mcf_graph g(N); REP(i,M){ int 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); } cout << g.flow(0, N-1, 2).second << endl; } int main(){ cin.tie(0); ios::sync_with_stdio(false); solve(); // int T; cin >> T; REP(t,T) solve(); }