結果
問題 | No.1301 Strange Graph Shortest Path |
ユーザー |
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提出日時 | 2020-11-28 16:46:35 |
言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 294 ms / 3,000 ms |
コード長 | 5,019 bytes |
コンパイル時間 | 2,097 ms |
コンパイル使用メモリ | 190,224 KB |
実行使用メモリ | 36,452 KB |
最終ジャッジ日時 | 2024-09-12 23:14:25 |
合計ジャッジ時間 | 11,702 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge4 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 33 |
ソースコード
/*** @FileName a.cpp* @Author kanpurin* @Created 2020.11.28 16:46:30**/#include "bits/stdc++.h"using namespace std;typedef long long ll;template <typename Cap, typename Cost>struct MininumCostFlow {private:struct _edge {int to, rev;Cap cap;Cost cost;};int _n;std::vector<std::pair<int, int>> pos;std::vector<std::vector<_edge>> g;public:MininumCostFlow() {}MininumCostFlow(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);int m = int(pos.size());pos.push_back({from, int(g[from].size())});g[from].push_back(_edge{to, int(g[to].size()), cap, cost});g[to].push_back(_edge{from, int(g[from].size()) - 1, 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<edge> edges() {int m = int(pos.size());std::vector<edge> result(m);for (int i = 0; i < m; i++) {result[i] = get_edge(i);}return result;}std::pair<Cap, Cost> flow(int s, int t) {return flow(s, t, std::numeric_limits<Cap>::max());}std::pair<Cap, Cost> flow(int s, int t, Cap flow_limit) {return slope(s, t, flow_limit).back();}std::vector<std::pair<Cap, Cost>> slope(int s, int t) {return slope(s, t, std::numeric_limits<Cap>::max());}std::vector<std::pair<Cap, Cost>> slope(int s, int t, Cap flow_limit) {assert(0 <= s && s < _n);assert(0 <= t && t < _n);assert(s != t);std::vector<Cost> dual(_n, 0), dist(_n);std::vector<int> pv(_n), pe(_n);std::vector<bool> vis(_n);auto dual_ref = [&]() {std::fill(dist.begin(), dist.end(), std::numeric_limits<Cost>::max());std::fill(pv.begin(), pv.end(), -1);std::fill(pe.begin(), pe.end(), -1);std::fill(vis.begin(), vis.end(), false);struct Q {Cost key;int to;bool operator<(Q r) const { return key > r.key; }};std::priority_queue<Q> que;dist[s] = 0;que.push(Q{0, s});while (!que.empty()) {int v = que.top().to;que.pop();if (vis[v]) continue;vis[v] = true;if (v == t) break;for (int i = 0; i < int(g[v].size()); i++) {auto e = g[v][i];if (vis[e.to] || !e.cap) continue;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(Q{dist[e.to], e.to});}}}if (!vis[t]) {return false;}for (int v = 0; v < _n; v++) {if (!vis[v]) continue;dual[v] -= dist[t] - dist[v];}return true;};Cap flow = 0;Cost cost = 0, prev_cost = -1;std::vector<std::pair<Cap, Cost>> 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 == d) {result.pop_back();}result.push_back({flow, cost});prev_cost = cost;}return result;}void print() {for(auto e : this->edges()) {cout << e.from << "->" << e.to << " [" << e.flow << "/" << e.cap << "], cost = " << e.cost << endl;}}};int main() {int n,m;cin >> n >> m;MininumCostFlow<ll,ll> g(n+1);for (int i = 0; i < m; i++) {int u,v,a,b;cin >> u >> v >> a >> b;u--;v--;g.add_edge(u,v,1,a);g.add_edge(u,v,1,b);g.add_edge(v,u,1,a);g.add_edge(v,u,1,b);}g.add_edge(n,0,2,0);cout << g.flow(n,n-1).second << endl;return 0;}