diff options
Diffstat (limited to 'I_anno/Programmazione_2/data_structures/graph_stl.cc')
-rw-r--r-- | I_anno/Programmazione_2/data_structures/graph_stl.cc | 221 |
1 files changed, 0 insertions, 221 deletions
diff --git a/I_anno/Programmazione_2/data_structures/graph_stl.cc b/I_anno/Programmazione_2/data_structures/graph_stl.cc deleted file mode 100644 index 5381747..0000000 --- a/I_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; -} |