#692315 (C++17) No.957 植林

• 問題: No.957 植林
• ユーザー: hitonanode
• 提出日時: 2021-08-25 22:00:41
• 言語: C++17 (gcc 13.3.0 + boost 1.89.0)
• 結果: AC
• 実行時間: 179 ms / 2,000 ms
• コード長: 4,496 bytes
• コンパイル時間: 1,305 ms
• コンパイル使用メモリ: 93,716 KB
• 最終ジャッジ日時: 2025-01-24 01:51:21
• ジャッジサーバーID （参考情報）: judge1 / judge3

ファイルパターン	結果
sample	AC * 3
other	AC * 45

ソースコード

#line 1 "combinatorial_opt/test/maxflow.pushrelabel.yuki957.test.cpp"
#define PROBLEM "https://yukicoder.me/problems/no/957"
#line 2 "combinatorial_opt/maxflow_pushrelabel.hpp"
#include <cassert>
#include <limits>
#include <utility>
#include <vector>

// Maxflow (push-relabel, highest-label)
// Complexity: O(N^2 M^(1/2))
template <class Cap, Cap INF = std::numeric_limits<Cap>::max() / 2, bool UseGlobalLabeling = false>
struct mf_pushrelabel {
    int _n;
    struct _edge {
        int to, rev;
        Cap cap;
    };
    std::vector<std::vector<_edge>> g;
    std::vector<std::pair<int, int>> pos;
    mf_pushrelabel(int n) : _n(n), g(n) { static_assert(INF > 0, "INF must be positive."); }
    int add_edge(int from, int to, Cap cap) {
        assert(0 <= from and from < _n);
        assert(0 <= to and to < _n);
        assert(0 <= cap);
        int m = int(pos.size());
        pos.emplace_back(from, int(g[from].size()));
        int from_id = g[from].size(), to_id = g[to].size() + (from == to);
        g[from].push_back({to, to_id, cap});
        g[to].push_back({from, from_id, Cap(0)});
        return m;
    }

    std::vector<int> dist;
    std::vector<Cap> excess;
    std::vector<std::vector<int>> h2v;
    int max_height;
    void activate(int i) {
        h2v[dist[i]].push_back(i);
        if (dist[i] > max_height) max_height = dist[i];
    }
    void global_labeling(int t) {
        if (!UseGlobalLabeling) return;
        dist.assign(_n, _n), dist[t] = 0;
        static std::vector<int> q;
        q = {t};
        int qh = 0;
        h2v.assign(_n * 2, {});
        max_height = -1;
        while (qh < int(q.size())) {
            int now = q[qh++];
            if (excess[now] > 0) activate(now);
            for (const auto &e : g[now]) {
                if (g[e.to][e.rev].cap and dist[e.to] == _n) {
                    dist[e.to] = dist[now] + 1;
                    q.push_back(e.to);
                }
            }
        }
    }
    Cap flow(const int &s, const int &t) {
        assert(0 <= s and s < _n);
        assert(0 <= t and t < _n);
        assert(s != t);
        excess.assign(_n, 0);
        excess[s] = INF, excess[t] = -INF;
        dist.assign(_n, 0);
        dist[s] = _n;
        h2v.assign(_n * 2, {});
        max_height = -1;
        for (auto &e : g[s]) push(s, e);
        global_labeling(t);
        int tick = _n;
        while (max_height >= 0) {
            if (h2v[max_height].empty()) {
                max_height--;
                continue;
            }
            int i = h2v[max_height].back();
            h2v[max_height].pop_back();
            int dnxt = _n * 2 - 1;
            for (auto &e : g[i]) {
                if (!e.cap) continue;
                if (dist[e.to] == dist[i] - 1) {
                    push(i, e);
                    if (excess[i] == 0) break;
                } else {
                    if (dist[e.to] + 1 < dnxt) dnxt = dist[e.to] + 1;
                }
            }
            if (excess[i] > 0) {
                dist[i] = dnxt;
                activate(i);
            }
            if (--tick == 0) tick = _n, global_labeling(t);
        }
        return excess[t] + INF;
    }

    void push(int i, _edge &e) {
        Cap delta = e.cap < excess[i] ? e.cap : excess[i];
        excess[i] -= delta, e.cap -= delta;
        excess[e.to] += delta, g[e.to][e.rev].cap += delta;
        if (excess[e.to] > 0 and excess[e.to] <= delta) activate(e.to);
    }
};
#line 3 "combinatorial_opt/test/maxflow.pushrelabel.yuki957.test.cpp"
#include <algorithm>
#include <iostream>
#include <numeric>
using namespace std;

int main() {
    cin.tie(nullptr), ios::sync_with_stdio(false);
    int H, W;
    cin >> H >> W;
    vector<vector<int>> G(H, vector<int>(W));
    for (auto &v : G) {
        for (auto &x : v) cin >> x;
    }
    vector<int> R(H), C(W);
    for (auto &x : R) cin >> x;
    for (auto &x : C) cin >> x;
    long long tot = accumulate(R.begin(), R.end(), 0LL) + accumulate(C.begin(), C.end(), 0LL);

    long long f1 = 0;

    int Z = 1 + H + W;
    mf_pushrelabel<long long> g(Z + 1);

    for (int i = 0; i < H; i++) {
        auto gtot = accumulate(G[i].begin(), G[i].end(), 0LL);
        auto f0 = min<long long>(gtot, R[i]);
        f1 += f0;
        g.add_edge(0, i + 1, gtot - f0);
        for (int j = 0; j < W; j++) g.add_edge(i + 1, H + 1 + j, G[i][j]);
    }
    for (int j = 0; j < W; j++) g.add_edge(H + 1 + j, Z, C[j]);
    cout << tot - f1 - g.flow(0, Z) << '\n';
}