92 lines
2.0 KiB
C++
92 lines
2.0 KiB
C++
#ifndef FRIGIONI_H_
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#define FRIGIONI_H_
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#include "algorithm/roditty_zwick.h"
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#include "algorithm/tarjan.h"
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#include "graph/breadth_first_tree.h"
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#include "algorithm/decremental_scc.h"
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#include <forward_list>
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#include <utility>
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#include <iostream>
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using namespace graph;
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namespace algo {
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template<typename T>
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class Frigioni : public RodittyZwick<T> {
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public:
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Frigioni(Digraph<T> G) : G(G) {}
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void init();
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bool query(const T& u, const T& v);
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void remove(const T& u, const T& v);
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private:
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Digraph<T> G;
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// Transitive closure matrix, used to answer reachability queries in O(1)
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std::map<T, std::map<T, bool>> TC;
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// Connect each vertex with its representative SCC
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std::map<T, SCC<T>> C;
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// Each scc's representative vertex reachability tree
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std::map<T, BreadthFirstTree<T>> RT;
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// Incoming / Outgoing / Internal edges
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struct Edges {
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std::set<std::pair<T, T>> in;
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std::set<std::pair<T, T>> inc;
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std::set<std::pair<T, T>> out;
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};
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std::map<T, Edges> E;
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};
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template<typename T>
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void Frigioni<T>::init() {
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auto SCCs = Tarjan<T>(G.adjMatrix).execute();
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for (auto& scc : SCCs) {
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RT[scc.id] = BreadthFirstTree<T>(G, scc.id);
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for (const auto& u : G.vertices()) {
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C[u] = scc;
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for (const auto& v : G.adjMatrix[u]) {
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TC[u][v] = false;
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if (scc.member(u)) {
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if (scc.member(v))
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E[scc.id].in.insert(std::make_pair(u, v));
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else
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E[scc.id].out.insert(std::make_pair(u, v));
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} else if (scc.member(v)) {
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E[scc.id].inc.insert(std::make_pair(u, v));
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}
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}
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}
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}
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for (auto& scc : SCCs) {
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for (const auto& u : G.vertices()) {
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if (scc.member(u)) {
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for (const auto& v : RT[scc.id].vertices()) {
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TC[u][v] = true;
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}
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}
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}
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}
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}
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template<typename T>
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bool Frigioni<T>::query(const T& u, const T& v) {
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return TC[u][v];
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}
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template<typename T>
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void Frigioni<T>::remove(const T& u, const T& v) {
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}
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} // namespace algo
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#endif |