test/graph/kruskal.aoj_ALDS1_12_A.test.cpp

View this file on GitHub
Last update: 2022-12-17 23:55:47+09:00
Problem: https://onlinejudge.u-aizu.ac.jp/problems/ALDS1_12_A

Depends on

Code

#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/problems/ALDS1_12_A"

#include <iostream>

#include "graph/minimumSpanningTree.hpp"
#include "macros.hpp"
using namespace std;

int main() {
  int N;
  long long c;
  cin >> N;
  Edges<long long> edges;
  rep(i, N) {
    rep(j, N) {
      cin >> c;
      if (c != -1) edges.emplace_back(i, j, c);
    }
  }
  MinimumSpanningTree<long long> mst = kruskal(edges, N);
  cout << mst.cost << endl;
}

#line 1 "test/graph/kruskal.aoj_ALDS1_12_A.test.cpp"
#define PROBLEM "https://onlinejudge.u-aizu.ac.jp/problems/ALDS1_12_A"

#include <iostream>

#line 2 "graph/graphTemplate.hpp"
#include <vector>
#line 4 "graph/graphTemplate.hpp"
using namespace std;

template <typename T = int>
struct Edge {
  int from, to;
  T cost;
  int idx;
  Edge() = default;

  Edge(int from, int to, T cost = 1, int idx = -1)
      : from(from), to(to), cost(cost), idx(idx) {}
  operator int() const { return to; }
};

template <typename T = int>
struct Graph {
  vector<vector<Edge<T>>> g;
  int es;

  Graph() = default;
  explicit Graph(int n) : g(n), es(0) {}

  size_t size() const { return g.size(); }

  void add_directed_edge(int from, int to, T cost = 1) {
    g[from].emplace_back(from, to, cost, es++);
  }

  void add_edge(int from, int to, T cost = 1) {
    g[from].emplace_back(from, to, cost, es);
    g[to].emplace_back(to, from, cost, es++);
  }
  void read(int M, int padding = -1, bool weighted = false,
            bool directed = false) {
    for (int i = 0; i < M; i++) {
      int a, b;
      cin >> a >> b;
      a += padding;
      b += padding;
      T c = T(1);
      if (weighted) {
        cin >> c;
      }
      if (directed) {
        add_directed_edge(a, b, c);
      } else {
        add_edge(a, b, c);
      }
    }
  }
  inline vector<Edge<T>> &operator[](const int &k) { return g[k]; }

  inline const vector<Edge<T>> &operator[](const int &k) const { return g[k]; }
};

template <typename T>
using Edges = vector<Edge<T>>;
#line 2 "structure/unionFind.hpp"
#include <algorithm>
#line 4 "structure/unionFind.hpp"

struct UnionFind {
  std::vector<int> data;
  UnionFind() = default;

  explicit UnionFind(size_t sz) : data(sz, -1) {}

  bool unite(int a, int b) {
    a = find(a);
    b = find(b);
    if (a == b) return false;
    if (data[a] < data[b]) std::swap(a, b);
    data[a] += data[b];
    data[b] = a;
    return true;
  }

  int find(int a) {
    if (data[a] < 0) return a;
    return data[a] = find(data[a]);
  }

  int same(int a, int b) { return find(a) == find(b); }

  int size(int k) { return -data[find(k)]; }

  std::vector<std::vector<int>> groups() {
    int n = (int)data.size();
    std::vector<std::vector<int>> ret(n);
    for (int i = 0; i < n; i++) {
      ret[find(i)].emplace_back(i);
    }
    ret.erase(std::remove_if(std::begin(ret), std::end(ret),
                        [&](const std::vector<int>& v) { return v.empty(); }),
              std::end(ret));
    return ret;
  }
};
#line 4 "graph/minimumSpanningTree.hpp"

template <typename T>
struct MinimumSpanningTree {
  T cost;
  Edges<T> edges;
};

template <typename T>
MinimumSpanningTree<T> kruskal(Edges<T> &edges, int V) {
  sort(begin(edges), end(edges),
       [](const Edge<T> &a, const Edge<T> &b) { return a.cost < b.cost; });
  UnionFind uf(V);
  T total = T();
  Edges<T> es;
  for (auto &e : edges) {
    if (uf.unite(e.from, e.to)) {
      es.emplace_back(e);
      total += e.cost;
    }
  }
  return {total, es};
}
#line 2 "macros.hpp"
#define rep(i, n) for (int i = 0; i < (n); i++)
#line 7 "test/graph/kruskal.aoj_ALDS1_12_A.test.cpp"
using namespace std;

int main() {
  int N;
  long long c;
  cin >> N;
  Edges<long long> edges;
  rep(i, N) {
    rep(j, N) {
      cin >> c;
      if (c != -1) edges.emplace_back(i, j, c);
    }
  }
  MinimumSpanningTree<long long> mst = kruskal(edges, N);
  cout << mst.cost << endl;
}