#include using namespace std; #define rep(i, n) for(int i = 0; i < n; i++) #define rep2(i, x, n) for(int i = x; i <= n; i++) #define rep3(i, x, n) for(int i = x; i >= n; i--) #define each(e, v) for(auto &e: v) #define pb push_back #define eb emplace_back #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define sz(x) (int)x.size() using ll = long long; using pii = pair; using pil = pair; using pli = pair; using pll = pair; const int MOD = 1000000007; //const int MOD = 998244353; const int inf = (1<<30)-1; const ll INF = (1LL<<60)-1; template bool chmax(T &x, const T &y) {return (x < y)? (x = y, true) : false;}; template bool chmin(T &x, const T &y) {return (x > y)? (x = y, true) : false;}; struct io_setup{ io_setup(){ ios_base::sync_with_stdio(false); cin.tie(NULL); cout << fixed << setprecision(15); } } io_setup; template struct Min_Cost_Flow{ struct edge{ int to; T cap, cost; int rev; edge(int to, T cap, T cost, int rev) : to(to), cap(cap), cost(cost), rev(rev) {} }; vector> es; vector d, h; vector pre_v, pre_e; const T INF_T; const int n; Min_Cost_Flow(int n) : INF_T(numeric_limits::max()), n(n){ es.resize(n), d.resize(n), h.resize(n), pre_v.resize(n), pre_e.resize(n); } void add_edge(int from, int to, T cap, T cost){ es[from].eb(to, cap, cost, sz(es[to])); es[to].eb(from, 0, -cost, sz(es[from])-1); } void bellman_ford(int s){ fill(all(h), INF_T); h[s] = 0; while(true){ bool update = false; rep(i, n){ if(h[i] == INF_T) continue; each(e, es[i]){ if(e.cap > 0 && chmin(h[e.to], h[i]+e.cost)){ update = true; } } } if(!update) break; } } void dijkstra(int s){ fill(all(d), INF_T); using P = pair; priority_queue, greater

> que; que.emplace(d[s] = 0, s); while(!que.empty()){ auto [p, i] = que.top(); que.pop(); if(p > d[i]) continue; rep(j, sz(es[i])){ edge &e = es[i][j]; if(e.cap > 0 && chmin(d[e.to], d[i]+e.cost+h[i]-h[e.to])){ pre_v[e.to] = i, pre_e[e.to] = j; que.emplace(d[e.to], e.to); } } } } T min_cost_flow(int s, int t, T flow){ T ret = 0; fill(all(h), 0); //bellman_ford(s); while(flow > 0){ dijkstra(s); if(d[t] == INF_T) return -1; rep(i, sz(es)){ if(h[i] == INF_T || d[i] == INF_T) h[i] = INF_T; else h[i] += d[i]; } T f = flow; for(int now = t; now != s; now = pre_v[now]){ chmin(f, es[pre_v[now]][pre_e[now]].cap); } ret += f*h[t], flow -= f; for(int now = t; now != s; now = pre_v[now]){ edge &e = es[pre_v[now]][pre_e[now]]; e.cap -= f, es[now][e.rev].cap += f; } } return ret; } }; int main(){ int N, M; cin >> N >> M; Min_Cost_Flow G(N); while(M--){ int u, v; ll 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.min_cost_flow(0, N-1, 2) << '\n'; }