summaryrefslogtreecommitdiff
path: root/1_anno/Programmazione_2/data_structures/graph_stl.cc
diff options
context:
space:
mode:
Diffstat (limited to '1_anno/Programmazione_2/data_structures/graph_stl.cc')
-rw-r--r--1_anno/Programmazione_2/data_structures/graph_stl.cc221
1 files changed, 0 insertions, 221 deletions
diff --git a/1_anno/Programmazione_2/data_structures/graph_stl.cc b/1_anno/Programmazione_2/data_structures/graph_stl.cc
deleted file mode 100644
index 5381747..0000000
--- a/1_anno/Programmazione_2/data_structures/graph_stl.cc
+++ /dev/null
@@ -1,221 +0,0 @@
-#include<iostream>
-#include<vector>
-#include<algorithm>
-#include<queue>
-#include<stack>
-#define INF 99999999
-#define W -1
-#define G 0
-#define B 1
-
-using namespace std;
-
-template<class H>
-class graph {
-public:
- graph(int len) : _len{len}, _nodes{0}, _edges{0} {
- _k = new H*[len];
- _adj = new vector<int>[len];
- _colors = new int[len];
- _d = new int[len];
- _f = new int[len];
- _p = new int[len];
-
- for(int i = 0; i < len; ++i) {
- _k[i] = nullptr;
- }
- }
- ~graph() {
- delete[] _k;
- delete[] _adj;
- }
-
- graph<H>* add_node(H x) {
- if(_index(x) > -1) return this;
- if(_nodes == _len) return this;
- _k[_nodes++] = new H(x);
-
- return this;
- }
- graph<H>* add_edge(H u, H v) {
- int i = _index(u);
- int j = _index(v);
- if(i < 0 || j < 0) return this;
-
- if(find(_adj[i].begin(), _adj[i].end(), j) == _adj[i].end()) {
- _adj[i].push_back(j);
- }
- return this;
- }
- void print() {
- for(int i = 0; i < _nodes; ++i) {
- cout << "(" << *_k[i] << ", " << i << "): ";
- for(auto const& j : _adj[i]) {
- cout << "(" << *_k[j] << ", " << j << ") ";
- }
- cout << endl;
- }
- }
- void dfsvisit(int u, bool visited[]) {
- visited[u] = true;
- cout << "(" << *_k[u] << ", " << u << ") ";
- for(auto const& i : _adj[u]) {
- if(!visited[i])
- dfsvisit(i, visited);
- }
- }
- int dfsvisit(int u) {
- int cycle = 0;
- _colors[u] = G;
- _d[u] = _time++;
-
- for(auto const& j : _adj[u]) {
- if(_colors[j] == W)
- cycle |= dfsvisit(j);
- }
-
- _colors[u] = B;
- _stack.push(u);
- _f[u] = _time++;
- return cycle;
- }
- int dfs() {
- int cycle = 0;
- for(int i = 0; i < _nodes; ++i) {
- _colors[i] = W;
- }
- _time = 0;
- for(int i = 0; i < _nodes; ++i) {
- if(_colors[i] == W)
- cycle |= dfsvisit(i);
- else if(_colors[i] == G)
- cycle = 1;
- }
- for(int i = 0; i < _nodes; ++i) {
- cout << "(" << *_k[i] << ", " << i << "): [" << _d[i] << "," << _f[i] << "]" << endl;
- }
- return cycle;
- }
-
- void top_sort() {
- int cycle = dfs();
- if(cycle) {
- cout << "cyclic graph!" << endl;
- return;
- }
- int* s = new int[_nodes];
- for(int i = 0; i < _nodes; ++i) s[i] = i;
- _sort(s, _nodes, _f);
- for(int i = 0; i < _nodes; ++i) {
- cout << "(" << s[i] << ", " << _f[s[i]] << ") ";
- }
-
- }
-
- void bfs(H v) {
- int s = _index(v);
- if(s < 0) return;
-
- for(int i = 0; i < _nodes; ++i) {
- _colors[i] = W;
- _d[i] = INF;
- _p[i] = -1;
- }
- _colors[s] = G;
- _d[s] = 0;
- queue<int> q;
- q.push(s);
- while(!q.empty()) {
- int u = q.front();
- q.pop();
- for(auto const& j : _adj[u]) {
- if(_colors[j] == W) {
- _colors[j] = G;
- _d[j] = _d[u]+1;
- _p[j] = u;
- q.push(j);
- }
- }
- _colors[u] = B;
- }
- for(int i = 0; i < _nodes; ++i) {
- cout << "(" << *_k[i] << ", " << i << "): [" << _d[i] << "]" << endl;
- }
- }
- void ssc() {
- dfs();
- cout << endl << endl;
- auto gr = _transpose();
- bool* visited = new bool[_nodes];
- for(int i = 0; i < _nodes; ++i)
- visited[i] = false;
-
- while(!_stack.empty()) {
- int v = _stack.top();
- _stack.pop();
- if(!visited[v]) {
- gr->dfsvisit(v, visited);
- cout << endl;
- }
- }
- delete[] visited;
- }
-private:
- graph<H>* _transpose() {
- graph<H>* g = new graph<H>{_len};
- for(int i = 0; i < _nodes; ++i) {
- g->add_node(*_k[i]);
- }
-
- for(int i = 0; i < _nodes; ++i) {
- for(auto const& j : _adj[i]) {
- g->add_edge(j, i);
- }
- }
-
- return g;
- }
- void _sort(int* d, int n, int* s) {
- for(int i = -1; i < n; ++i) {
- int j = i-1;
- while(j > -1 && s[d[j+1]]>s[d[j]]) {
- swap(d[s[j+1]], d[s[j]]);
- --j;
- }
- }
- }
- int _index(H x) {
- for(int i = 0; i < _nodes; ++i)
- if(*_k[i] == x) return i;
-
- return -1;
- }
- stack<int> _stack;
- H** _k;
- vector<int>* _adj;
- int _len, _nodes, _edges;
- int* _colors;
- int _time;
- int* _d;
- int* _f;
- int* _p;
-};
-
-int main() {
- graph<int>* g = new graph<int>{5};
- for(auto const& i : {0, 1, 2, 3, 4})
- g->add_node(i);
- g->add_edge(1, 0);
- g->add_edge(2, 1);
- g->add_edge(0, 2);
- g->add_edge(0, 3);
- g->add_edge(3, 4);
- //g->print();
- cout << endl;
- //g->top_sort();
- g->ssc();
- cout << endl;
- //g->bfs(0);
- delete g;
- return 0;
-}