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stefiosif
2024-08-03 13:14:42 +03:00
parent d216a9611f
commit 3951db7ff9
17 changed files with 262 additions and 287 deletions
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34
include/algorithm/breadth_first_search.h
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@@ -1,35 +1,38 @@
#ifndef BREADTH_FIRST_SEARCH_H_
#define BREADTH_FIRST_SEARCH_H_
#include "graph/graph.h"
#include <map>
#include <set>
#include <queue>
#include <set>
using namespace graph;
namespace algo {
template<typename T>
class BreadthFirstSearch {
template <typename T> class BreadthFirstSearch {
public:
BreadthFirstSearch() = default;
explicit BreadthFirstSearch(std::unordered_map<T, std::unordered_set<T>> adjList)
: adjList(adjList) {}
explicit BreadthFirstSearch(
std::unordered_map<T, std::unordered_set<T>> adjList)
: adjList(adjList) {}
// Traverse whole graph using the BFS search, and save the tree graph
// which is created when visiting new vertices (Breadth First Tree)
std::unordered_map<T, std::unordered_set<T>> execute(const T& root);
std::unordered_map<T, std::unordered_set<T>> execute(const T &root);
// Search if target vertex exists in graph
bool query(const T& root, const T& target);
bool query(const T &root, const T &target);
private:
// Represents the graph on which the algorithm will be executed
std::unordered_map<T, std::unordered_set<T>> adjList;
};
};
template<typename T>
std::unordered_map<T, std::unordered_set<T>> BreadthFirstSearch<T>::execute(const T& root) {
template <typename T>
std::unordered_map<T, std::unordered_set<T>>
BreadthFirstSearch<T>::execute(const T &root) {
std::unordered_map<T, std::unordered_set<T>> tree;
std::unordered_map<T, bool> visited;
std::queue<T> Q;
@@ -40,7 +43,7 @@ std::unordered_map<T, std::unordered_set<T>> BreadthFirstSearch<T>::execute(cons
const auto v = Q.front();
Q.pop();
for (const auto& u : adjList[v]) {
for (const auto &u : adjList[v]) {
if (!visited[u]) {
visited[u] = true;
tree[v].insert(u);
@@ -52,8 +55,8 @@ std::unordered_map<T, std::unordered_set<T>> BreadthFirstSearch<T>::execute(cons
return tree;
}
template<typename T>
bool BreadthFirstSearch<T>::query(const T& root, const T& target) {
template <typename T>
bool BreadthFirstSearch<T>::query(const T &root, const T &target) {
std::unordered_map<T, bool> visited;
std::queue<T> Q;
Q.push(root);
@@ -63,9 +66,10 @@ bool BreadthFirstSearch<T>::query(const T& root, const T& target) {
const auto v = Q.front();
Q.pop();
if (v == target) return true;
if (v == target)
return true;
for (const auto& u : adjList[v]) {
for (const auto &u : adjList[v]) {
if (!visited[u]) {
visited[u] = true;
Q.push(u);

11
include/algorithm/decremental_reachability.h
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@@ -4,21 +4,20 @@
#include "graph/digraph.h"
namespace algo {
template<typename T>
class DecrementalReachability {
template <typename T> class DecrementalReachability {
public:
virtual ~DecrementalReachability() = default;
// This method is implemented and executed by all roditty and zwick
// algorithms, it constructs the data structures used in other operations
virtual void init() =0;
virtual void init() = 0;
// Answer if vertex v is reachable from vertex u
virtual bool query(const T& u, const T& v) =0;
virtual bool query(const T &u, const T &v) = 0;
// Remove edge e(u,v) and maintain the transitive closure matrix
virtual void remove(const std::vector<std::pair<T, T>>& edges) =0;
virtual void remove(const std::vector<std::pair<T, T>> &edges) = 0;
protected:
Digraph<T> G;
};

6
include/algorithm/dynamic_reachability.h
View File

@@ -4,15 +4,13 @@
#include "algorithm/decremental_reachability.h"
namespace algo {
template<typename T>
template <typename T>
class DynamicReachability : public DecrementalReachability<T> {
// Insert edge e(u,v) and maintain the transitive closure matrix
virtual void insert(const T& c, const std::vector<T>& vertices) =0;
virtual void insert(const T &c, const std::vector<T> &vertices) = 0;
};
} // namespace algo
#endif

143
include/algorithm/frigioni.h
View File

@@ -8,8 +8,7 @@
namespace algo {
template<typename T>
class Frigioni : public DecrementalReachability<T> {
template <typename T> class Frigioni : public DecrementalReachability<T> {
public:
Frigioni() = default;
@@ -20,10 +19,11 @@ public:
// Execute reachability query q(u, v) from vertex u to vertex v
// in O(1) using the transitive closure matrix
bool query(const T& u, const T& v) override;
bool query(const T &u, const T &v) override;
// Delete set of edges and explicitely maintain the transitive closure
void remove(const std::vector<std::pair<T, T>>& edges) override;
void remove(const std::vector<std::pair<T, T>> &edges) override;
private:
// Transitive closure matrix, used to answer reachability queries in O(1)
std::unordered_map<T, std::unordered_map<T, bool>> TC;
@@ -46,161 +46,162 @@ private:
RodittyZwick<T> rodittyZwick;
// Delete internal edge e(u, v)
void removeInternal(const T& u, const T& v);
void removeInternal(const T &u, const T &v);
// Delete external edge e(u, v)
void removeExternal(const T& u, const T& v);
void removeExternal(const T &u, const T &v);
// Repair reachability trees
void repairTrees();
//
void splitEdges(std::unordered_map<T, SCC<T>>& L, std::unordered_map<T, SCC<T>> C, const T& w);
//
void splitEdges(std::unordered_map<T, SCC<T>> &L,
std::unordered_map<T, SCC<T>> C, const T &w);
};
template<typename T>
void Frigioni<T>::init() {
template <typename T> void Frigioni<T>::init() {
rodittyZwick = RodittyZwick<T>(this->G);
rodittyZwick.init();
auto C = rodittyZwick.getComponentMap();
for (const auto& w : std::views::keys(C)) {
for (const auto &w : std::views::keys(C)) {
RT[C[w]] = BreadthFirstTree<T>(this->G, w);
for (const auto& u : this->G.vertices()) {
for (const auto& v : this->G.adjList[u]) {
for (const auto &u : this->G.vertices()) {
for (const auto &v : this->G.adjList[u]) {
if (!C[w].contains(u) && C[w].contains(v))
E[C[w]].inc.insert({ u, v });
E[C[w]].inc.insert({u, v});
else if (C[w].contains(u) && !C[w].contains(v))
E[C[w]].out.insert({ u, v });
E[C[w]].out.insert({u, v});
else
E[C[w]].in.insert({ u, v });
E[C[w]].in.insert({u, v});
TC[u][v] = false;
}
}
}
for (const auto& w : std::views::keys(C)) {
for (const auto& u : C[w].vertices()) {
for (const auto& v : RT[C[w]].vertices()) {
for (const auto &w : std::views::keys(C)) {
for (const auto &u : C[w].vertices()) {
for (const auto &v : RT[C[w]].vertices()) {
TC[u][v] = true;
}
}
}
}
template<typename T>
bool Frigioni<T>::query(const T& u, const T& v) {
template <typename T> bool Frigioni<T>::query(const T &u, const T &v) {
return TC[u][v];
}
template<typename T>
void Frigioni<T>::remove(const std::vector<std::pair<T, T>>& edges) {
template <typename T>
void Frigioni<T>::remove(const std::vector<std::pair<T, T>> &edges) {
std::vector<std::pair<T, T>> Eint;
std::vector<std::pair<T, T>> Eext;
for (const auto& [u, v] : edges) {
if (!this->G.adjList[u].contains(v)) continue;
for (const auto &[u, v] : edges) {
if (!this->G.adjList[u].contains(v))
continue;
if (rodittyZwick.query(u, v))
Eint.push_back({ u, v });
Eint.push_back({u, v});
else
Eext.push_back({ u, v });
Eext.push_back({u, v});
}
for (const auto& [u, v] : Eint) removeInternal(u, v);
for (const auto& [u, v] : Eext) removeExternal(u, v);
for (const auto &[u, v] : Eint)
removeInternal(u, v);
for (const auto &[u, v] : Eext)
removeExternal(u, v);
repairTrees();
}
template<typename T>
void Frigioni<T>::removeInternal(const T& u, const T& v) {
template <typename T> void Frigioni<T>::removeInternal(const T &u, const T &v) {
this->G.remove(u, v);
auto L = rodittyZwick.getComponentMap();
rodittyZwick.remove(u, v);
auto C = rodittyZwick.getComponentMap();
if (rodittyZwick.query(u, v)) {
E[C[u]].in.erase({ u, v });
E[C[u]].in.erase({u, v});
return;
}
if (L[u] == C[u]) {
E[L[u]].out.erase({ u, v });
E[L[u]].out.erase({u, v});
E.erase(L[v]);
splitEdges(L, C, v);
}
else {
E[L[v]].inc.erase({ u, v });
} else {
E[L[v]].inc.erase({u, v});
E.erase(L[u]);
splitEdges(L, C, u);
}
for (const auto& w : std::views::keys(C)) {
if (!RT[C[w]].contains(v)) continue;
for (const auto &w : std::views::keys(C)) {
if (!RT[C[w]].contains(v))
continue;
RT[C[w]].removeEdgeTo(v);
if (E[C[v]].inc.size() > 0) {
H[C[w]].push(v); /*h mipos C[v].id?*/
continue;
}
for (const auto& x : C[w].vertices()) {
for (const auto& y : C[v].vertices()) {
for (const auto &x : C[w].vertices()) {
for (const auto &y : C[v].vertices()) {
TC[x][y] = false;
}
}
for (const auto& [a, b] : E[C[v]].out)
for (const auto &[a, b] : E[C[v]].out)
H[C[w]].push(b);
}
}
template<typename T>
void Frigioni<T>::removeExternal(const T& u, const T& v) {
template <typename T> void Frigioni<T>::removeExternal(const T &u, const T &v) {
this->G.remove(u, v);
auto C = rodittyZwick.getComponentMap();
E[C[v]].inc.erase({ u, v });
E[C[u]].out.erase({ u, v });
E[C[v]].inc.erase({u, v});
E[C[u]].out.erase({u, v});
for (const auto& w : std::views::keys(C)) {
if (!RT[C[w]].contains(v)) continue;
for (const auto &w : std::views::keys(C)) {
if (!RT[C[w]].contains(v))
continue;
RT[C[w]].removeEdgeTo(v);
if (E[C[v]].inc.size() > 0) {
H[C[w]].push(v);
continue;
}
for (const auto& x : C[w].vertices()) {
for (const auto& y : C[v].vertices()) {
for (const auto &x : C[w].vertices()) {
for (const auto &y : C[v].vertices()) {
TC[x][y] = false;
}
}
for (const auto& [a, b] : E[C[v]].out)
for (const auto &[a, b] : E[C[v]].out)
H[C[w]].push(b);
}
}
template<typename T>
void Frigioni<T>::repairTrees() {
template <typename T> void Frigioni<T>::repairTrees() {
auto C = rodittyZwick.getComponentMap();
for (const auto& w : std::views::keys(C)) {
for (const auto &w : std::views::keys(C)) {
while (H[C[w]].size() > 0) {
const auto& h = H[C[w]].top();
const auto &h = H[C[w]].top();
H[C[w]].pop();
bool foundHook = false;
for (const auto& [a, b] : E[C[h]].inc) {
for (const auto &[a, b] : E[C[h]].inc) {
if (RT[C[w]].adjList[w].contains(a)) {
RT[C[w]].insert(a, h);
foundHook = true;
break;
}
}
if (foundHook) continue;
if (foundHook)
continue;
for (const auto& x : C[w].vertices()) {
for (const auto& y : C[h].vertices()) {
for (const auto &x : C[w].vertices()) {
for (const auto &y : C[h].vertices()) {
TC[x][y] = false;
}
}
for (const auto& [a, b] : E[C[h]].out) {
for (const auto &[a, b] : E[C[h]].out) {
if (RT[C[w]].adjList[h].contains(a)) {
H[C[w]].push(b);
}
@@ -209,21 +210,21 @@ void Frigioni<T>::repairTrees() {
}
}
template<typename T>
void Frigioni<T>::splitEdges(std::unordered_map<T, SCC<T>>& L, std::unordered_map<T, SCC<T>> C, const T& w) {
for (const auto& [a, b] : E[L[w]].inc)
E[C[b]].inc.insert({ a, b });
template <typename T>
void Frigioni<T>::splitEdges(std::unordered_map<T, SCC<T>> &L,
std::unordered_map<T, SCC<T>> C, const T &w) {
for (const auto &[a, b] : E[L[w]].inc)
E[C[b]].inc.insert({a, b});
for (const auto& [a, b] : E[L[w]].out)
E[C[a]].out.insert({ a, b });
for (const auto &[a, b] : E[L[w]].out)
E[C[a]].out.insert({a, b});
for (const auto& [a, b] : E[L[w]].in) {
for (const auto &[a, b] : E[L[w]].in) {
if (C[a] == C[b]) {
E[C[a]].in.insert({ a, b });
}
else {
E[C[a]].out.insert({ a, b });
E[C[b]].in.insert({ a, b });
E[C[a]].in.insert({a, b});
} else {
E[C[a]].out.insert({a, b});
E[C[b]].in.insert({a, b});
}
}
}

38
include/algorithm/henzinger_king.h
View File

@@ -8,8 +8,7 @@ constexpr int threshold = 5;
namespace algo {
template<typename T>
class HenzingerKing : public DynamicReachability<T> {
template <typename T> class HenzingerKing : public DynamicReachability<T> {
public:
HenzingerKing() = default;
@@ -21,16 +20,17 @@ public:
// Execute query q(u, v) from vertex u to vertex v by querying the
// decremental reachability data structure at the start of the phase
// and then if necessary check the set S
bool query(const T& u, const T& v) override;
bool query(const T &u, const T &v) override;
// Remove collection of edges from the decremental maintenance data structure
// and for every vertex in set S, rebuilt reachability trees from scratch
void remove(const std::vector<std::pair<T,T>>& edges);
void remove(const std::vector<std::pair<T, T>> &edges) override;
// Insert collection of edges in set S, if threshold is reached re-initialize
// algorithm, otherwise construct reachability trees for the vertex that is
// the center-of-insertions
void insert(const T& c, const std::vector<T>& vertices);
void insert(const T &c, const std::vector<T> &vertices) override;
private:
// Decremental maintenance data structure
Frigioni<T> frigioni;
@@ -43,41 +43,37 @@ private:
std::unordered_map<T, BreadthFirstTree<T>> Out;
};
template<typename T>
void HenzingerKing<T>::init() {
template <typename T> void HenzingerKing<T>::init() {
S.clear();
frigioni = Frigioni<T>(this->G);
frigioni.init();
}
template<typename T>
bool HenzingerKing<T>::query(const T& u, const T& v) {
template <typename T> bool HenzingerKing<T>::query(const T &u, const T &v) {
if (frigioni.query(u, v))
return true;
return std::ranges::any_of(S.begin(), S.end(),
[&](const T& w) {
return In[w].adjList.contains(u) &&
Out[w].adjList.contains(v);
});
return std::ranges::any_of(S.begin(), S.end(), [&](const T &w) {
return In[w].adjList.contains(u) && Out[w].adjList.contains(v);
});
}
template<typename T>
void HenzingerKing<T>::remove(const std::vector<std::pair<T, T>>& edges) {
for (const auto& [u, v] : edges) {
template <typename T>
void HenzingerKing<T>::remove(const std::vector<std::pair<T, T>> &edges) {
for (const auto &[u, v] : edges) {
this->G.remove(u, v);
}
frigioni.remove(edges);
for (const auto& w : S) {
for (const auto &w : S) {
In[w] = BreadthFirstTree(this->G.reverse(), w);
Out[w] = BreadthFirstTree(this->G, w);
}
}
template<typename T>
void HenzingerKing<T>::insert(const T& c, const std::vector<T>& vertices) {
for (const auto& w : vertices)
template <typename T>
void HenzingerKing<T>::insert(const T &c, const std::vector<T> &vertices) {
for (const auto &w : vertices)
this->G.insert(c, w);
S.insert(c);

59
include/algorithm/italiano.h
View File

@@ -7,8 +7,7 @@
namespace algo {
template<typename T>
class Italiano : public DecrementalReachability<T> {
template <typename T> class Italiano : public DecrementalReachability<T> {
public:
Italiano() = default;
@@ -19,17 +18,18 @@ public:
// Execute reachability query q(u, v) from vertex u to vertex v
// in O(1) using the transitive closure matrix
bool query(const T& u, const T& v) override;
bool query(const T &u, const T &v) override;
// Delete collection of edges
void remove(const std::vector<std::pair<T, T>>& edges) override;
void remove(const std::vector<std::pair<T, T>> &edges) override;
// Delete edge e(u, v) and explicitly maintain the transitive closure
void remove(const T& u, const T& v);
void remove(const T &u, const T &v);
private:
// Transitive closure matrix
std::unordered_map<T, std::unordered_map<T, bool>> TC;
// For each vertex, store a reachability tree created as a BFS tree
std::unordered_map<T, BreadthFirstTree<T>> RT;
@@ -47,42 +47,41 @@ private:
void repairTrees();
};
template<typename T>
void Italiano<T>::init() {
for (const auto& u : this->G.vertices()) {
for (const auto& v : this->G.adjList[u]) {
template <typename T> void Italiano<T>::init() {
for (const auto &u : this->G.vertices()) {
for (const auto &v : this->G.adjList[u]) {
E[v].inc.insert(u);
E[u].out.insert(v);
TC[u][v] = false;
}
RT[u] = BreadthFirstTree<T>(this->G, u);
TC[u][u] = true;
for (const auto& v : RT[u].vertices())
for (const auto &v : RT[u].vertices())
TC[u][v] = true;
}
}
template<typename T>
bool Italiano<T>::query(const T& u, const T& v) {
template <typename T> bool Italiano<T>::query(const T &u, const T &v) {
return TC[u][v];
}
template<typename T>
void Italiano<T>::remove(const std::vector<std::pair<T, T>>& edges) {
for (const auto& [u, v] : edges) {
if (!this->G.adjList[u].contains(v)) continue;
template <typename T>
void Italiano<T>::remove(const std::vector<std::pair<T, T>> &edges) {
for (const auto &[u, v] : edges) {
if (!this->G.adjList[u].contains(v))
continue;
remove(u, v);
}
}
template<typename T>
void Italiano<T>::remove(const T& u, const T& v) {
template <typename T> void Italiano<T>::remove(const T &u, const T &v) {
this->G.remove(u, v);
E[u].out.erase(v);
E[v].inc.erase(u);
for (const auto& w : this->G.vertices()) {
if (!RT[w].adjList[u].contains(v)) continue;
for (const auto &w : this->G.vertices()) {
if (!RT[w].adjList[u].contains(v))
continue;
RT[w].adjList[u].erase(v);
if (E[v].inc.size() > 0) {
@@ -90,31 +89,31 @@ void Italiano<T>::remove(const T& u, const T& v) {
continue;
}
TC[w][v] = false;
for (const auto& c : E[v].out)
for (const auto &c : E[v].out)
H[w].push(c);
}
repairTrees();
}
template<typename T>
void Italiano<T>::repairTrees() {
for (const auto& w : this->G.vertices()) {
template <typename T> void Italiano<T>::repairTrees() {
for (const auto &w : this->G.vertices()) {
while (H[w].size() > 0) {
const auto& h = H[w].top();
const auto &h = H[w].top();
H[w].pop();
bool foundHook = false;
for (const auto& i : E[h].inc) {
for (const auto &i : E[h].inc) {
if (RT[w].adjList[w].contains(i)) {
RT[w].adjList[i].insert(h);
foundHook = true;
break;
}
}
if (foundHook) continue;
if (foundHook)
continue;
TC[w][h] = false;
for (const auto& o : E[h].out) {
for (const auto &o : E[h].out) {
if (RT[w].adjList[h].contains(o)) {
H[w].push(o);
}

44
include/algorithm/king.h
View File

@@ -6,8 +6,7 @@
namespace algo {
template<typename T>
class King : public DynamicReachability<T> {
template <typename T> class King : public DynamicReachability<T> {
public:
King() = default;
@@ -19,26 +18,26 @@ public:
// Execute reachability query q(u, v) from vertex u to vertex v
// in O(n) using the stored decremental maintenance data structure for DAGs
bool query(const T& u, const T& v) override;
bool query(const T &u, const T &v) override;
// Delete collection of edges
void remove(const std::vector<std::pair<T, T>>& edges) override;
void remove(const std::vector<std::pair<T, T>> &edges) override;
// Delete edge e(u, v) from all reachability trees and update each one of
// them using the decremental reachability algorithm for DAGs
void remove(const T& u, const T& v);
void remove(const T &u, const T &v);
// Insert edge e(u, v) by reconstructing all reachability trees
void insert(const T& c, const std::vector<T>& vertices) override;
void insert(const T &c, const std::vector<T> &vertices) override;
private:
// Connect each reachabiliy tree with decremental maintenance data structure
std::unordered_map<T, Italiano<T>> In;
std::unordered_map<T, Italiano<T>> Out;
};
template<typename T>
void King<T>::init() {
for (const auto& u : this->G.vertices()) {
template <typename T> void King<T>::init() {
for (const auto &u : this->G.vertices()) {
In[u] = Italiano<T>(BreadthFirstTree<T>(this->G.reverse(), u));
In[u].init();
Out[u] = Italiano<T>(BreadthFirstTree<T>(this->G, u));
@@ -46,32 +45,29 @@ void King<T>::init() {
}
}
template<typename T>
bool King<T>::query(const T& u, const T& v) {
return std::ranges::any_of(this->G.vertices().begin(), this->G.vertices().end(),
[&](const T& w) {
return In[w].query(w, u) && Out[w].query(w, v);
});
template <typename T> bool King<T>::query(const T &u, const T &v) {
return std::any_of(
this->G.vertices().begin(), this->G.vertices().end(),
[&](const T &w) { return In[w].query(w, u) && Out[w].query(w, v); });
}
template<typename T>
void King<T>::remove(const std::vector<std::pair<T, T>>& edges) {
for (const auto& [u, v] : edges)
template <typename T>
void King<T>::remove(const std::vector<std::pair<T, T>> &edges) {
for (const auto &[u, v] : edges)
remove(u, v);
}
template<typename T>
void King<T>::remove(const T& u, const T& v) {
template <typename T> void King<T>::remove(const T &u, const T &v) {
this->G.remove(u, v);
for (const auto& w : this->G.vertices()) {
for (const auto &w : this->G.vertices()) {
In[w].remove(v, u);
Out[w].remove(u, v);
}
}
template<typename T>
void King<T>::insert(const T& c, const std::vector<T>& vertices) {
for (const auto& v : vertices) {
template <typename T>
void King<T>::insert(const T &c, const std::vector<T> &vertices) {
for (const auto &v : vertices) {
this->G.insert(c, v);
}
In[c] = Italiano<T>(BreadthFirstTree<T>(this->G.reverse(), c));

47
include/algorithm/roditty_zwick.h
View File

@@ -7,8 +7,7 @@
namespace algo {
template<typename T>
class RodittyZwick : public DecrementalReachability<T> {
template <typename T> class RodittyZwick : public DecrementalReachability<T> {
public:
RodittyZwick() = default;
@@ -21,15 +20,16 @@ public:
void findSCC(graph::Digraph<T> G);
// Return true if u and v are in the same SCC
bool query(const T& u, const T& v) override;
bool query(const T &u, const T &v) override;
// Delete collection of edges
void remove(const std::vector<std::pair<T, T>>& edges) override;
void remove(const std::vector<std::pair<T, T>> &edges) override;
// Remove edge (u,v) and update A accordingly for fast checking query
void remove(const T& u, const T& v);
void remove(const T &u, const T &v);
std::unordered_map<T, SCC<T>> getComponentMap() { return C; }
private:
// Array used to answer strong connectivity queries in O(1) time
std::unordered_map<T, T> A;
@@ -42,21 +42,17 @@ private:
std::unordered_map<T, BreadthFirstTree<T>> Out;
};
template<typename T>
void RodittyZwick<T>::init() {
findSCC(this->G);
}
template <typename T> void RodittyZwick<T>::init() { findSCC(this->G); }
template<typename T>
void RodittyZwick<T>::findSCC(graph::Digraph<T> G) {
template <typename T> void RodittyZwick<T>::findSCC(graph::Digraph<T> G) {
auto SCCs = Tarjan<T>(G.adjList).execute();
for (auto& c : SCCs) {
const auto& w = c.id;
for (const auto& v : c.vertices())
for (auto &c : SCCs) {
const auto &w = c.id;
for (const auto &v : c.vertices())
A[v] = w;
Out[w] = BreadthFirstTree<T>(c, w);
In[w] = BreadthFirstTree<T>(c.reverse(), w);
@@ -64,20 +60,18 @@ void RodittyZwick<T>::findSCC(graph::Digraph<T> G) {
}
}
template<typename T>
bool RodittyZwick<T>::query(const T& u, const T& v) {
template <typename T> bool RodittyZwick<T>::query(const T &u, const T &v) {
return A[u] == A[v];
}
template<typename T>
void RodittyZwick<T>::remove(const std::vector<std::pair<T, T>>& edges) {
for (const auto& [u, v] : edges)
template <typename T>
void RodittyZwick<T>::remove(const std::vector<std::pair<T, T>> &edges) {
for (const auto &[u, v] : edges)
remove(u, v);
}
template<typename T>
void RodittyZwick<T>::remove(const T& u, const T& v) {
const auto& w = A[u];
template <typename T> void RodittyZwick<T>::remove(const T &u, const T &v) {
const auto &w = A[u];
C[w].remove(u, v);
this->G.remove(u, v);
@@ -85,8 +79,9 @@ void RodittyZwick<T>::remove(const T& u, const T& v) {
if (A[u] != A[v])
return;
// If edge (u,v) is not contained in both inTree and outTree do nothing TODO:remove useless comments
// is this not better if i utilize A matrix, since we are going traversing between components.. ? TODO
// If edge (u,v) is not contained in both inTree and outTree do nothing
// TODO:remove useless comments is this not better if i utilize A matrix,
// since we are going traversing between components.. ? TODO
if (!In[w].adjList[u].contains(v) && !Out[w].adjList[u].contains(v))
return;

27
include/algorithm/tarjan.h
View File

@@ -3,24 +3,25 @@
#include "graph/scc.h"
#include <ranges>
#include <stack>
#include <vector>
#include <ranges>
namespace algo {
template<typename T>
class Tarjan {
template <typename T> class Tarjan {
public:
Tarjan() = default;
explicit Tarjan(std::unordered_map<T, std::unordered_set<T>> adjList) : adjList(adjList) {}
explicit Tarjan(std::unordered_map<T, std::unordered_set<T>> adjList)
: adjList(adjList) {}
//
auto execute();
//
void strongConnect(const T& u);
void strongConnect(const T &u);
private:
std::unordered_map<T, std::unordered_set<T>> adjList;
std::stack<T> S;
@@ -36,13 +37,12 @@ private:
std::unordered_map<T, Vertex> V;
};
template<typename T>
void Tarjan<T>::strongConnect(const T& u) {
template <typename T> void Tarjan<T>::strongConnect(const T &u) {
V[u].index = V[u].lowlink = index++;
S.push(u);
V[u].onStack = true;
for (const auto& w : adjList[u]) {
for (const auto &w : adjList[u]) {
if (V[w].index == -1) {
strongConnect(w);
V[u].lowlink = std::min(V[u].lowlink, V[w].lowlink);
@@ -64,14 +64,13 @@ void Tarjan<T>::strongConnect(const T& u) {
scc[w] = adjList[w];
finished = (w == u);
} while (!finished);
SCCs.push_back({ scc, static_cast<T>(cid) });
SCCs.push_back({scc, static_cast<T>(cid)});
}
}
template<typename T>
auto Tarjan<T>::execute() {
for (const auto& u : std::views::keys(adjList)) {
template <typename T> auto Tarjan<T>::execute() {
for (const auto &u : std::views::keys(adjList)) {
if (V[u].index == -1)
strongConnect(u);
}