Luzhiled's Library

This documentation is automatically generated by competitive-verifier/competitive-verifier

View the Project on GitHub ei1333/library

:heavy_check_mark: test/verify/aoj-1615.test.cpp

Depends on

Code

// competitive-verifier: PROBLEM http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1615

#include "../../template/template.hpp"

#include "../../graph/flow/dinic.hpp"
#include "../../graph/flow/maxflow-lower-bound.hpp"

int main() {
  int N, M;
  while(cin >> N >> M, N) {
    vector< int > U(M), V(M);
    for(int i = 0; i < M; i++) {
      cin >> U[i] >> V[i];
      --U[i], --V[i];
    }
    auto check = [&](int low, int high) {
      MaxFlowLowerBound< int, Dinic > flow(N + M + 2);
      int S = N + M, T = N + M + 1;
      for(int i = 0; i < M; i++) {
        flow.add_edge(S, i, 1, 1);
        flow.add_edge(i, M + U[i], 0, 1);
        flow.add_edge(i, M + V[i], 0, 1);
      }
      for(int i = 0; i < N; i++) {
        flow.add_edge(M + i, T, low, high);
      }
      return flow.max_flow(S, T) == M;
    };

    int p = 0, q = N;
    int l = 0;
    for(int r = 0; r <= N; r++) {
      while(l <= r && check(l, r)) {
        p = l, q = r;
        ++l;
      }
    }
    cout << p << " " << q << endl;
  }
}

#line 1 "test/verify/aoj-1615.test.cpp"
// competitive-verifier: PROBLEM http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1615

#line 1 "template/template.hpp"
#include <bits/stdc++.h>
#if __has_include(<atcoder/all>)
#include <atcoder/all>
#endif

using namespace std;

using int64 = long long;

const int64 infll = (1LL << 62) - 1;
const int inf = (1 << 30) - 1;

struct IoSetup {
  IoSetup() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);
    cerr << fixed << setprecision(10);
  }
} iosetup;

template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
  os << p.first << " " << p.second;
  return os;
}

template <typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
  is >> p.first >> p.second;
  return is;
}

template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
  for (int i = 0; i < (int)v.size(); i++) {
    os << v[i] << (i + 1 != v.size() ? " " : "");
  }
  return os;
}

template <typename T>
istream &operator>>(istream &is, vector<T> &v) {
  for (T &in : v) is >> in;
  return is;
}

template <typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {
  return a < b && (a = b, true);
}

template <typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {
  return a > b && (a = b, true);
}

template <typename T = int64>
vector<T> make_v(size_t a) {
  return vector<T>(a);
}

template <typename T, typename... Ts>
auto make_v(size_t a, Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}

template <typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type fill_v(T &t, const V &v) {
  t = v;
}

template <typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type fill_v(T &t, const V &v) {
  for (auto &e : t) fill_v(e, v);
}

template <typename F>
struct FixPoint : F {
  explicit FixPoint(F &&f) : F(std::forward<F>(f)) {}

  template <typename... Args>
  decltype(auto) operator()(Args &&...args) const {
    return F::operator()(*this, std::forward<Args>(args)...);
  }
};

template <typename F>
inline decltype(auto) MFP(F &&f) {
  return FixPoint<F>{std::forward<F>(f)};
}
#line 4 "test/verify/aoj-1615.test.cpp"

#line 1 "graph/flow/dinic.hpp"
/**
 * @brief Dinic(最大流)
 *
 */
template <typename flow_t>
struct Dinic {
  const flow_t INF;

  struct edge {
    int to;
    flow_t cap;
    int rev;
    bool isrev;
    int idx;
  };

  vector<vector<edge> > graph;
  vector<int> min_cost, iter;

  explicit Dinic(int V) : INF(numeric_limits<flow_t>::max()), graph(V) {}

  void add_edge(int from, int to, flow_t cap, int idx = -1) {
    graph[from].emplace_back(
        (edge){to, cap, (int)graph[to].size(), false, idx});
    graph[to].emplace_back(
        (edge){from, 0, (int)graph[from].size() - 1, true, idx});
  }

  bool build_augment_path(int s, int t) {
    min_cost.assign(graph.size(), -1);
    queue<int> que;
    min_cost[s] = 0;
    que.push(s);
    while (!que.empty() && min_cost[t] == -1) {
      int p = que.front();
      que.pop();
      for (auto &e : graph[p]) {
        if (e.cap > 0 && min_cost[e.to] == -1) {
          min_cost[e.to] = min_cost[p] + 1;
          que.push(e.to);
        }
      }
    }
    return min_cost[t] != -1;
  }

  flow_t find_min_dist_augment_path(int idx, const int t, flow_t flow) {
    if (idx == t) return flow;
    for (int &i = iter[idx]; i < (int)graph[idx].size(); i++) {
      edge &e = graph[idx][i];
      if (e.cap > 0 && min_cost[idx] < min_cost[e.to]) {
        flow_t d = find_min_dist_augment_path(e.to, t, min(flow, e.cap));
        if (d > 0) {
          e.cap -= d;
          graph[e.to][e.rev].cap += d;
          return d;
        }
      }
    }
    return 0;
  }

  flow_t max_flow(int s, int t) {
    flow_t flow = 0;
    while (build_augment_path(s, t)) {
      iter.assign(graph.size(), 0);
      flow_t f;
      while ((f = find_min_dist_augment_path(s, t, INF)) > 0) flow += f;
    }
    return flow;
  }

  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 << "/"
             << e.cap + rev_e.cap << ")" << endl;
      }
    }
  }

  vector<bool> min_cut(int s) {
    vector<bool> used(graph.size());
    queue<int> que;
    que.emplace(s);
    used[s] = true;
    while (not que.empty()) {
      int p = que.front();
      que.pop();
      for (auto &e : graph[p]) {
        if (e.cap > 0 and not used[e.to]) {
          used[e.to] = true;
          que.emplace(e.to);
        }
      }
    }
    return used;
  }
};
#line 1 "graph/flow/maxflow-lower-bound.hpp"
template <typename flow_t, template <typename> class F>
struct MaxFlowLowerBound {
  F<flow_t> flow;
  vector<flow_t> in, up;
  typename F<flow_t>::edge *latte, *malta;
  int X, Y, V;
  flow_t sum;

  MaxFlowLowerBound(int V) : flow(V + 2), in(V), X(V), Y(V + 1), V(V), sum(0) {}

  void add_edge(int from, int to, flow_t low, flow_t high) {
    assert(from != to);
    flow.add_edge(from, to, high - low, up.size());
    in[from] -= low;
    in[to] += low;
    up.emplace_back(high);
  }

  void build() {
    for (int i = 0; i < V; i++) {
      if (in[i] > 0) {
        flow.add_edge(X, i, in[i]);
        sum += in[i];
      } else if (in[i] < 0) {
        flow.add_edge(i, Y, -in[i]);
      }
    }
  }

  bool can_flow(int s, int t) {
    assert(s != t);
    flow.add_edge(t, s, flow.INF);
    latte = &flow.graph[t].back();
    malta = &flow.graph[s].back();
    return can_flow();
  }

  bool can_flow() {
    build();
    auto ret = flow.max_flow(X, Y);
    return ret >= sum;
  }

  flow_t max_flow(int s, int t) {
    if (can_flow(s, t)) {
      return flow.max_flow(s, t);
    } else {
      return -1;
    }
  }

  flow_t min_flow(int s, int t) {
    if (can_flow(s, t)) {
      auto ret = flow.INF - latte->cap;
      latte->cap = malta->cap = 0;
      return ret - flow.max_flow(t, s);
    } else {
      return -1;
    }
  }

  void output(int M) {
    vector<flow_t> ans(M);
    for (int i = 0; i < flow.graph.size(); i++) {
      for (auto &e : flow.graph[i]) {
        if (!e.isrev && ~e.idx) ans[e.idx] = up[e.idx] - e.cap;
      }
    }
    for (auto &p : ans) cout << p << endl;
  }
};
#line 7 "test/verify/aoj-1615.test.cpp"

int main() {
  int N, M;
  while(cin >> N >> M, N) {
    vector< int > U(M), V(M);
    for(int i = 0; i < M; i++) {
      cin >> U[i] >> V[i];
      --U[i], --V[i];
    }
    auto check = [&](int low, int high) {
      MaxFlowLowerBound< int, Dinic > flow(N + M + 2);
      int S = N + M, T = N + M + 1;
      for(int i = 0; i < M; i++) {
        flow.add_edge(S, i, 1, 1);
        flow.add_edge(i, M + U[i], 0, 1);
        flow.add_edge(i, M + V[i], 0, 1);
      }
      for(int i = 0; i < N; i++) {
        flow.add_edge(M + i, T, low, high);
      }
      return flow.max_flow(S, T) == M;
    };

    int p = 0, q = N;
    int l = 0;
    for(int r = 0; r <= N; r++) {
      while(l <= r && check(l, r)) {
        p = l, q = r;
        ++l;
      }
    }
    cout << p << " " << q << endl;
  }
}

Test cases

Env Name Status Elapsed Memory
g++ testcase_00 :heavy_check_mark: AC 354 ms 4 MB
g++ testcase_01 :heavy_check_mark: AC 336 ms 5 MB
clang++ testcase_00 :heavy_check_mark: AC 369 ms 4 MB
clang++ testcase_01 :heavy_check_mark: AC 347 ms 5 MB
Back to top page