graph/minimum-spanning-tree.hpp

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• Last update: 1970-01-01 00:00:00+00:00
• Include: #include "graph/minimum-spanning-tree.hpp"

Code

#pragma once

#include "../data-structure/union-find.hpp"
#include "./base.hpp"
#include "./graph-type.hpp"

#include <queue>

namespace matumoto {

  template <typename Cost>
  struct MinimumSpanningTree {
    vector<pair<Cost, int>> graph_;
    vector<pair<Cost, int>> mst_;
    MinimumSpanningTree(const vector<pair<Cost, int>> &graph): graph_(graph) {}

    Cost kruskal() {
      mst_ = vector<pair<Cost, int>>(graph_.size()); // init
      if (graph_.size() == 0) {
        return Cost(0);
      }

      vector<WeightedEdge<Cost>> edges = graph_.edges();
      sort(edges.begin(), edges.end());

      matumoto::UnionFind uf(graph_.size());

      Cost sum = 0;

      for (auto edge: edges) {
        int from = edge.from();
        int to = edge.to();

        if (uf.same(from, to))
          continue;

        uf.merge(from, to);
        sum += edge.cost();
        mst_.add_edge(edge);
      }

      return sum;
    }

    Cost prim() {
      mst_ = vector<pair<Cost, int>>(graph_.size()); // init
      if (graph_.size() == 0) {
        return Cost(0);
      }

      priority_queue<WeightedEdge<Cost>, vector<WeightedEdge<Cost>>, greater<WeightedEdge<Cost>>> pq;
      pq.emplace(/*from=*/0, /*to=*/0, Cost(0));

      vector<vector<WeightedEdge<Cost>>> adj_list = graph_.graph();
      vector<bool> used(graph_.size(), false);

      Cost sum = 0;

      while (not pq.empty()) {
        auto e = pq.top();
        pq.pop();

        int v = e.to();

        if (used[v])
          continue;

        sum += e.cost();
        used[v] = true;
        mst_.add_edge(e);

        for (auto edge: adj_list[v]) {
          int to = edge.to();

          if (used[to])
            continue;

          pq.push(edge);
        }
      }

      return sum;
    }
  };

} // namespace matumoto

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.11.4/x64/lib/python3.11/site-packages/onlinejudge_verify/documentation/build.py", line 71, in _render_source_code_stat
    bundled_code = language.bundle(stat.path, basedir=basedir, options={'include_paths': [basedir]}).decode()
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/hostedtoolcache/Python/3.11.4/x64/lib/python3.11/site-packages/onlinejudge_verify/languages/cplusplus.py", line 187, in bundle
    bundler.update(path)
  File "/opt/hostedtoolcache/Python/3.11.4/x64/lib/python3.11/site-packages/onlinejudge_verify/languages/cplusplus_bundle.py", line 401, in update
    self.update(self._resolve(pathlib.Path(included), included_from=path))
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/hostedtoolcache/Python/3.11.4/x64/lib/python3.11/site-packages/onlinejudge_verify/languages/cplusplus_bundle.py", line 260, in _resolve
    raise BundleErrorAt(path, -1, "no such header")
onlinejudge_verify.languages.cplusplus_bundle.BundleErrorAt: ../data-structure/union-find.hpp: line -1: no such header

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