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authorSanto Cariotti <dcariotti24@gmail.com>2020-10-18 18:56:43 +0200
committerSanto Cariotti <dcariotti24@gmail.com>2020-10-20 09:08:52 +0200
commitf279107065146a4940f5e73602a1c3c09e58b31d (patch)
treefd892749637a8b6c5c31ccb80bba04ade76ab87a /1_anno/Programmazione_2/data_structures
parent4e063e32250312c38d5646840719b62429362b21 (diff)
chore: name of first year folder
Diffstat (limited to '1_anno/Programmazione_2/data_structures')
-rw-r--r--1_anno/Programmazione_2/data_structures/bfs.cc186
-rw-r--r--1_anno/Programmazione_2/data_structures/bst.cc225
-rw-r--r--1_anno/Programmazione_2/data_structures/circle_double_list.cc185
-rw-r--r--1_anno/Programmazione_2/data_structures/circle_list.cc189
-rw-r--r--1_anno/Programmazione_2/data_structures/dfs.cc191
-rw-r--r--1_anno/Programmazione_2/data_structures/graph.cc164
-rw-r--r--1_anno/Programmazione_2/data_structures/graph_stl.cc221
-rw-r--r--1_anno/Programmazione_2/data_structures/list.cc164
-rw-r--r--1_anno/Programmazione_2/data_structures/list_double.cc182
-rw-r--r--1_anno/Programmazione_2/data_structures/matrix-graph.cc81
-rw-r--r--1_anno/Programmazione_2/data_structures/queue.cc72
-rw-r--r--1_anno/Programmazione_2/data_structures/queue_w_array.cc66
-rw-r--r--1_anno/Programmazione_2/data_structures/stack.cc70
-rw-r--r--1_anno/Programmazione_2/data_structures/stack_w_array.cc50
-rw-r--r--1_anno/Programmazione_2/data_structures/top-sort.cc212
15 files changed, 2258 insertions, 0 deletions
diff --git a/1_anno/Programmazione_2/data_structures/bfs.cc b/1_anno/Programmazione_2/data_structures/bfs.cc
new file mode 100644
index 0000000..2b4efbd
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/bfs.cc
@@ -0,0 +1,186 @@
+#include<iostream>
+#include<vector>
+#include<queue>
+#define W -1
+#define G 0
+#define B 1
+
+using namespace std;
+
+template<class H>
+class node {
+public:
+ explicit node(H key, node<H>* next) : _key{key}, _next(next) {}
+ const H& key() const { return _key; }
+ H& key() { return _key; }
+ const node<H>*& next() const { return _next; }
+ node<H>*& next() { return _next; }
+private:
+ H _key;
+ node<H>* _next;
+};
+
+template<class H>
+class list {
+public:
+ list() : _head{nullptr} {}
+ ~list() {
+ while(_head) {
+ auto tmp = _head;
+ _head = _head->next();
+ delete tmp;
+ }
+ }
+ list<H>* push(H val) {
+ auto iter = _head;
+ while(iter && iter->next())
+ iter = iter->next();
+
+ if(!iter)
+ _head = new node<H>{val, nullptr};
+ else
+ iter->next() = new node<H>{val, nullptr};
+
+ return this;
+ }
+ void print() {
+ auto iter = _head;
+ while(iter) {
+ cout << iter->key() << ' ';
+ iter = iter->next();
+ }
+ }
+ vector<H> as_vector() {
+ vector<H> v;
+ auto iter = _head;
+ while(iter) {
+ v.push_back(iter->key());
+ iter = iter->next();
+ }
+ return v;
+ }
+ node<H>* search(H val) {
+ auto iter = _head;
+ while(iter && iter->key() != val) {
+ iter = iter->next();
+ }
+
+ return iter;
+ }
+private:
+ node<H>* _head;
+};
+
+template<class H>
+class graph {
+public:
+
+private:
+ int _len, _nodes, _edges;
+ int* _parents;
+ int* _distances;
+ H** _k; // it works like a dictionary, it saves the keys
+ list<int>** _adj;
+ int _index(H val) {
+ for(int i = 0; i < _nodes; ++i)
+ if(*_k[i] == val) return i;
+
+ return -1;
+ }
+public:
+ graph(int len) : _len{len}, _nodes{0}, _edges{0} {
+ _k = new H*[len];
+ _adj = new list<int>*[_len];
+ _parents = new int[_len];
+ _distances = new int[_len];
+ for(int i = 0; i < _len; ++i) {
+ _k[i] = nullptr;
+ _adj[i] = new list<int>{};
+ }
+ }
+
+ graph<H>* add_node(H k) {
+ if(_nodes == _len) return this;
+ if(_index(k) >= 0) return this; // node is already there
+
+ _k[_nodes++] = new H(k);
+
+ return this;
+ }
+
+ void bfs(int s) {
+ int colors[_len];
+ queue<int> q;
+
+ for(int i = 0; i < _nodes; ++i) {
+ colors[i] = W;
+ _parents[i] = -1;
+ _distances[i] = 999999999;
+ }
+ q.push(s);
+ colors[s] = G;
+ _distances[s] = 0;
+ while(!q.empty()) {
+ int x = q.front();
+ q.pop();
+ for(auto const& j : _adj[x]->as_vector()) {
+ if(colors[j] == W) {
+ colors[j] = G;
+ q.push(j);
+ _parents[j] = x;
+ _distances[j] = _distances[x] + 1;
+ }
+ }
+ colors[x] = B;
+ }
+
+ for(int i = 0; i < _nodes; ++i) {
+ cout << "[" << i << "]->";
+ if(_distances[i]==999999999) cout << "inf." << endl;
+ else cout << _distances[i] << endl;
+ }
+ }
+
+ void bfs(H x) {
+ int s = _index(x);
+ if(s != -1)
+ bfs(s);
+ }
+
+ graph<H>* add_edge(H x, H y) {
+ int i = _index(x);
+ int j = _index(y);
+ if(i < 0 || j < 0) return this;
+
+ if(!_adj[i]->search(j)) {
+ _adj[i]->push(j);
+ _edges++;
+ }
+
+ return this;
+ }
+
+ void print() {
+ for(int i = 0; i < _nodes; ++i) {
+ cout << "(" << i << ", " << *_k[i] << "): ";
+ for(auto const& j : _adj[i]->as_vector())
+ cout << "(" << j << ", " << *_k[j] << "), ";
+ cout << '\n';
+ }
+ }
+};
+
+
+int main() {
+ graph<string>* g = new graph<string>(5);
+ g->add_node("hello")->add_node("greg")->add_node("yes");
+ g->add_node("nop")->add_node("ok");
+ g->add_edge("hello", "ok");
+ g->add_edge("ok", "yes")->add_edge("yes", "ok")->add_edge("yes", "yes");
+ g->add_edge("yes", "nop");
+ g->print();
+ g->bfs("hello");
+
+ delete g;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/bst.cc b/1_anno/Programmazione_2/data_structures/bst.cc
new file mode 100644
index 0000000..9223e04
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/bst.cc
@@ -0,0 +1,225 @@
+#include<iostream>
+
+using namespace std;
+
+template<class T>
+struct node {
+ T key;
+ node<T>* prev;
+ node<T>* right;
+ node<T>* left;
+};
+
+template<class T>
+class bst {
+public:
+ bst() : root{nullptr} {}
+
+ ~bst() {
+ // TODO
+ }
+
+ bst<T>* insert(initializer_list<T>&& list) {
+ for(auto const& i : list)
+ insert(i);
+
+ return this;
+ }
+
+ bst<T>* insert(T k) {
+ node<T>* nodus = new node<T>{k, nullptr, nullptr, nullptr};
+ node<T>* iter = root;
+ node<T>* prev = nullptr;
+
+ while(iter) {
+ prev = iter;
+ iter = (k < iter->key) ? iter->left : iter->right;
+ }
+
+ nodus->prev = prev;
+ if(!prev)
+ root = nodus;
+ else if(k < prev->key)
+ prev->left = nodus;
+ else
+ prev->right = nodus;
+
+ return this;
+ }
+
+ bst<T>* remove(initializer_list<T>&& list) {
+ for(auto const& i : list)
+ remove(i);
+
+ return this;
+ }
+
+ bst<T>* remove(T k) {
+ node<T>* nodus = search(k);
+ if(!nodus) return this;
+
+ if(!nodus->left) {
+ _transplant(nodus, nodus->right);
+ } else if(!nodus->right) {
+ _transplant(nodus, nodus->left);
+ } else {
+ node<T>* iter = _min(nodus->right);
+ if(iter->prev != nodus) {
+ _transplant(iter, iter->right);
+ iter->right = nodus->right;
+ iter->right->prev = iter;
+ }
+ _transplant(nodus, iter);
+ iter->left = nodus->left;
+ iter->left->prev = iter;
+ }
+
+ delete nodus;
+ return this;
+ }
+
+ node<T>* min() {
+ return _min(root);
+ }
+
+ node<T>* min(node<T>* nodus) {
+ return _min(nodus);
+ }
+
+ node<T>* max() {
+ return _max(root);
+ }
+
+ node<T>* max(node<T>* nodus) {
+ return _max(nodus);
+ }
+
+ node<T>* search(T k) {
+ node<T>* iter = root;
+ while(iter && iter->key != k)
+ iter = (iter->key > k) ? iter->left : iter->right;
+
+ return iter;
+ }
+
+ node<T>* successor(T k) {
+ node<T>* nodus = search(k);
+ if(!nodus) return nullptr;
+
+ if(nodus->right)
+ return min(nodus->right);
+
+ node<T>* prev = nodus->prev;
+ while(prev && nodus == prev->right) {
+ nodus = prev;
+ prev = prev->prev;
+ }
+
+ return prev;
+
+ }
+ node<T>* predecessor(T k) {
+ node<T>* nodus = search(k);
+ if(!nodus) return nullptr;
+
+ if(nodus->left)
+ return max(nodus->left);
+
+ node<T>* prev = nodus->prev;
+ while(prev && nodus == prev->left) {
+ nodus = prev;
+ prev = prev->prev;
+ }
+
+ return prev;
+ }
+
+ friend ostream& operator<<(ostream& os, bst<T>* tree) {
+ tree->_preorder(os, tree->root);
+ return os;
+ }
+private:
+ void _transplant(node<T>* u, node<T>* v) {
+ if(!u->prev) {
+ root = v;
+ } else if(u == u->prev->left) {
+ u->prev->left = v;
+ } else {
+ u->prev->right = v;
+ }
+
+ if(v)
+ v->prev = u->prev;
+ }
+
+ node<T>* _min(node<T>* root) {
+ node<T>* iter = root;
+ while(iter && iter->left)
+ iter = iter->left;
+
+ return iter;
+ }
+
+ node<T>* _max(node<T>* root) {
+ node<T>* iter = root;
+ while(iter && iter->right)
+ iter = iter->right;
+
+ return iter;
+ }
+
+ void _inorder(ostream& os, node<T>* root) {
+ if(root) {
+ _inorder(os, root->left);
+ os << root->key << ' ';
+ _inorder(os, root->right);
+ }
+ }
+
+ void _preorder(ostream& os, node<T>* root) {
+ if(root) {
+ os << root->key << ' ';
+ _inorder(os, root->left);
+ _inorder(os, root->right);
+ }
+ }
+
+ void _postorder(ostream& os, node<T>* root) {
+ if(root) {
+ _inorder(os, root->left);
+ _inorder(os, root->right);
+ os << root->key << ' ';
+ }
+ }
+ node<T>* root;
+};
+
+int main() {
+ bst<int>* b = new bst<int>{};
+
+ // b->insert(12)->insert(5)->insert(18)->insert(2)->insert(9);
+ // b->insert(15)->insert(13)->insert(17)->insert(19);
+
+ b->insert({12, 5, 18, 2, 9, 15, 13, 17, 19});
+ cout << b << endl;
+ cout << (b->search(5) != nullptr) << endl;
+ cout << (b->search(1) != nullptr) << endl;
+ cout << b->max()->key << ' ' << b->min()->key << endl;
+ for(auto const& i : {12, 9, 14, 18}) {
+ auto elem = b->successor(i);
+ if(elem)
+ cout << "(" << i << ", " << elem->key << ") ";
+ }
+ cout << endl;
+
+ for(auto const& i : {9, 2, 5, 15, 18, 12, 19}) {
+ auto elem = b->predecessor(i);
+ if(elem)
+ cout << "(" << i << ", " << elem->key << ") ";
+ }
+ cout << endl;
+ b->remove({5, 12});
+ cout << b << endl;
+
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/circle_double_list.cc b/1_anno/Programmazione_2/data_structures/circle_double_list.cc
new file mode 100644
index 0000000..f162e57
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/circle_double_list.cc
@@ -0,0 +1,185 @@
+#include<iostream>
+
+using namespace std;
+
+template<typename T>
+struct node {
+ T value;
+ node* prev;
+ node* next;
+};
+
+
+template<typename T>
+class list {
+public:
+ list() : _head{nullptr} {}
+
+ ~list() {
+ node<T>* iter = _head;
+ while(iter->next != _head) {
+ node<T>* tmp = iter;
+ delete tmp;
+ iter = iter->next;
+ }
+ node<T>* tmp = iter;
+ delete tmp;
+ }
+
+ list* push_front(T val) {
+ auto elem = _last();
+ if(!_head) {
+ _head = new node<T>{val, nullptr, nullptr};
+ _head->prev = _head->next = _head;
+ } else {
+ _head = new node<T>{val, elem, _head};
+ elem->next = _head->next->prev = _head;
+ }
+
+ return this;
+ }
+
+ list* push_back(T val) {
+ if(!_head) return this->push_front(val);
+
+ auto last_e = _last();
+ last_e->next = new node<T>{val, last_e, _head};
+ _head->prev = last_e->next;
+
+ return this;
+ }
+
+ list* push_after_value(T val, T newval) {
+ node<T>* iter = _search(val);
+ if(iter) {
+ node<T>* nod = new node<T>{newval, iter, iter->next};
+ iter->next = nod;
+ nod->next->prev = nod;
+ }
+
+ return this;
+ }
+
+ list* push_before_value(T val, T newval) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ node<T>* iter = _head;
+
+ if(iter->value == val)
+ return this->push_front(newval);
+
+ while(iter->next != elem)
+ iter = iter->next;
+
+ node<T>* nod = new node<T>{newval, iter, iter->next};
+ iter->next = nod;
+ nod->next->prev = nod;
+
+ return this;
+ }
+
+ list* pop(int val) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ if(elem == _head) return this->pop_front();
+
+ node<T>* iter = elem->prev;
+ node<T>* temp = iter->next;
+ iter->next = iter->next->next;
+ iter->next->prev = iter;
+ delete temp;
+
+ return this;
+ }
+
+ list* pop_front() {
+ if(!_head)
+ return this;
+
+ auto last_e = _last();
+ node<T>* elem = _head;
+ _head = _head->next;
+ _head->prev = last_e;
+ last_e->next = _head;
+ delete elem;
+
+ return this;
+ }
+
+ list* pop_back() {
+ if(!_head)
+ return this;
+
+ auto last_e = _last();
+
+ if(last_e == _head) {
+ delete _head;
+ _head = nullptr;
+ } else {
+ auto iter = last_e->prev;
+ delete iter->next;
+ iter->next = _head;
+ _head->prev = iter;
+ }
+
+ return this;
+ }
+
+ void print() {
+ node<T>* iter = _head;
+ while(iter != nullptr) {
+ cout << iter->value << ' ';
+ cout << "[[ " << iter->prev->value << ", ";
+ cout << iter->next->value << " ]], ";
+ iter = iter->next;
+ if(iter == _head) break;
+ }
+ }
+private:
+ node<T>* _last() {
+ node<T>* iter = _head;
+ while(iter && iter->next != _head) {
+ iter = iter->next;
+ }
+
+ return iter;
+ }
+
+ node<T>* _search(T val) {
+ node<T>* iter = _head;
+ if(iter->value == val) return iter;
+
+ while(iter && iter->value != val) {
+ iter = iter->next;
+ if(iter == _head) return nullptr;
+ }
+
+ return iter;
+ }
+
+ node<T>* _head;
+};
+
+int main() {
+ list<int>* l = new list<int>{};
+ l->push_front(2);
+ l->push_back(1)->push_back(3);
+ l->push_front(5)->push_front(9);
+ l->push_back(0)->push_back(6);
+ l->print(); cout << '\n';
+ l->push_after_value(7, -2);
+ l->push_before_value(9, 10);
+ l->print(); cout << '\n';
+ l->pop_front();
+ l->pop_front();
+ l->pop_back();
+ l->pop_front();
+ l->print(); cout << '\n';
+ l->pop(2);
+ l->print(); cout << '\n';
+
+ delete l;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/circle_list.cc b/1_anno/Programmazione_2/data_structures/circle_list.cc
new file mode 100644
index 0000000..2143ac1
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/circle_list.cc
@@ -0,0 +1,189 @@
+#include<iostream>
+
+using namespace std;
+
+template<typename T>
+struct node {
+ T value;
+ node* next;
+};
+
+
+template<typename T>
+class list {
+public:
+ list() : _head{nullptr} {}
+
+ ~list() {
+ node<T>* iter = _head;
+ while(iter->next != _head) {
+ node<T>* tmp = iter;
+ delete tmp;
+ iter = iter->next;
+ }
+ node<T>* tmp = iter;
+ delete tmp;
+ }
+
+ list* push_front(T val) {
+ auto elem = _last();
+ _head = new node<T>{val, _head};
+ if(!elem)
+ elem = _head;
+
+ elem->next = _head;
+
+ return this;
+ }
+
+ list* push_back(T val) {
+ if(!_head) return this->push_front(val);
+
+ auto last_e = _last();
+ last_e->next = new node<T>{val, _head};
+
+ return this;
+ }
+
+ list* push_after_value(T val, T newval) {
+ node<T>* iter = _search(val);
+ if(iter)
+ iter->next = new node<T>{newval, iter->next};
+
+ return this;
+ }
+
+ list* push_before_value(T val, T newval) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ node<T>* iter = _head;
+
+ if(iter->value == val)
+ return this->push_front(newval);
+
+ while(iter->next != elem)
+ iter = iter->next;
+
+ iter->next = new node<T>{newval, iter->next};
+
+ return this;
+ }
+
+ list* pop(int val) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ node<T>* iter = _head;
+ if(iter == elem) return this->pop_front();
+
+ while(iter->next != elem)
+ iter = iter->next;
+
+ node<T>* temp = iter->next;
+ iter->next = iter->next->next;
+ delete temp;
+
+ return this;
+ }
+
+ list* pop_front() {
+ if(!_head)
+ return this;
+
+ auto last_e = _last();
+
+ if(last_e == _head) {
+ delete _head;
+ _head = nullptr;
+ } else {
+ node<T>* elem = _head;
+ _head = _head->next;
+ last_e->next = _head;
+ delete elem;
+ }
+
+ return this;
+ }
+
+ list* pop_back() {
+ if(!_head)
+ return this;
+
+ node<T>* iter = _head;
+ auto last_e = _last();
+
+ if(last_e == _head) {
+ delete iter;
+ _head = nullptr;
+ } else {
+ while(iter->next != last_e) {
+ iter = iter->next;
+ }
+
+ delete iter->next;
+ iter->next = _head;
+ }
+
+ return this;
+ }
+
+ void print() {
+ node<T>* iter = _head;
+ while(iter) {
+ cout << iter->value << ' ';
+ iter = iter->next;
+ if(iter == _head) break;
+ }
+ }
+private:
+ node<T>* _last() {
+ node<T>* iter = _head;
+ while(iter && iter->next != _head) {
+ iter = iter->next;
+ }
+
+ return iter;
+ }
+
+ node<T>* _search(T val) {
+ node<T>* iter = _head;
+ if(iter->value == val) return iter;
+
+ while(iter && iter->value != val) {
+ iter = iter->next;
+ if(iter == _head) return nullptr;
+ }
+
+ return iter;
+ }
+
+ node<T>* _head;
+};
+
+int main() {
+ list<int>* l = new list<int>{};
+ l->push_before_value(4, 1);
+ l->push_back(4);
+ l->push_back(1);
+ l->push_back(0);
+ l->push_front(2);
+ l->print(); cout << endl;
+ l->pop_back();
+ l->print(); cout << endl;
+ l->pop_front();
+ l->print(); cout << endl;
+ l->pop_back();
+ l->print(); cout << endl;
+ l->push_front(3);
+ l->print(); cout << endl;
+ l->push_after_value(4, 7);
+ l->print(); cout << endl;
+ l->push_before_value(3, 5);
+ l->print(); cout << endl;
+ l->pop(5);
+ l->print(); cout << endl;
+
+ delete l;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/dfs.cc b/1_anno/Programmazione_2/data_structures/dfs.cc
new file mode 100644
index 0000000..744f153
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/dfs.cc
@@ -0,0 +1,191 @@
+#include<iostream>
+#include<vector>
+#include<queue>
+#define W -1
+#define G 0
+#define B 1
+
+using namespace std;
+
+template<class H>
+class node {
+public:
+ explicit node(H key, node<H>* next) : _key{key}, _next(next) {}
+ const H& key() const { return _key; }
+ H& key() { return _key; }
+ const node<H>*& next() const { return _next; }
+ node<H>*& next() { return _next; }
+private:
+ H _key;
+ node<H>* _next;
+};
+
+template<class H>
+class list {
+public:
+ list() : _head{nullptr} {}
+ ~list() {
+ while(_head) {
+ auto tmp = _head;
+ _head = _head->next();
+ delete tmp;
+ }
+ }
+ list<H>* push(H val) {
+ auto iter = _head;
+ while(iter && iter->next())
+ iter = iter->next();
+
+ if(!iter)
+ _head = new node<H>{val, nullptr};
+ else
+ iter->next() = new node<H>{val, nullptr};
+
+ return this;
+ }
+ void print() {
+ auto iter = _head;
+ while(iter) {
+ cout << iter->key() << ' ';
+ iter = iter->next();
+ }
+ }
+ vector<H> as_vector() {
+ vector<H> v;
+ auto iter = _head;
+ while(iter) {
+ v.push_back(iter->key());
+ iter = iter->next();
+ }
+ return v;
+ }
+ node<H>* search(H val) {
+ auto iter = _head;
+ while(iter && iter->key() != val) {
+ iter = iter->next();
+ }
+
+ return iter;
+ }
+private:
+ node<H>* _head;
+};
+
+template<class H>
+class graph {
+private:
+ int _len, _nodes, _edges;
+ int* _parents;
+ int* _radixes;
+ int* _distances;
+ int* _finishes;
+ int* _colors;
+ int _time;
+ int _current;
+ H** _k; // it works like a dictionary, it saves the keys
+ list<int>** _adj;
+ int _index(H val) {
+ for(int i = 0; i < _nodes; ++i)
+ if(*_k[i] == val) return i;
+
+ return -1;
+ }
+ void _dfsvisit(int u) {
+ _colors[u] = G;
+ _distances[u] = _time++;
+ _radixes[u] = _current;
+ for(auto const& v : _adj[u]->as_vector()) {
+ if(_colors[v] == W) {
+ _parents[v] = u;
+ _dfsvisit(v);
+ }
+ }
+ _colors[u] = B;
+ _finishes[u] = _time++;
+ }
+public:
+ graph(int len) : _len{len}, _nodes{0}, _edges{0} {
+ _k = new H*[len];
+ _adj = new list<int>*[_len];
+ _parents = new int[_len];
+ _radixes = new int[_len];
+ _distances = new int[_len];
+ _finishes = new int[_len];
+ _colors = new int[_len];
+ for(int i = 0; i < _len; ++i) {
+ _k[i] = nullptr;
+ _adj[i] = new list<int>{};
+ }
+ }
+
+ graph<H>* add_node(H k) {
+ if(_nodes == _len) return this;
+ if(_index(k) >= 0) return this; // node is already there
+
+ _k[_nodes++] = new H(k);
+
+ return this;
+ }
+
+
+ void dfs() {
+ _time = 0;
+ for(int i = 0; i < _nodes; ++i) {
+ _colors[i] = W;
+ _parents[i] = -1;
+ }
+
+ for(int i = 0; i < _nodes; ++i) {
+ if(_colors[i] == W) {
+ _current = i;
+ _dfsvisit(i);
+ }
+ }
+ for(int i = 0; i < _nodes; ++i) {
+ cout << *_k[i] << "(" << _distances[i]+1 << ',' << _finishes[i]+1 << ")" << endl;
+ }
+ }
+
+ graph<H>* add_edge(H x, H y) {
+ int i = _index(x);
+ int j = _index(y);
+ if(i < 0 || j < 0) return this;
+
+ if(!_adj[i]->search(j)) {
+ _adj[i]->push(j);
+ _edges++;
+ }
+
+ return this;
+ }
+
+ void print() {
+ for(int i = 0; i < _nodes; ++i) {
+ cout << "(" << i << ", " << *_k[i] << "): ";
+ for(auto const& j : _adj[i]->as_vector())
+ cout << "(" << j << ", " << *_k[j] << "), ";
+ cout << '\n';
+ }
+ }
+};
+
+
+int main() {
+ graph<char>* g = new graph<char>(6);
+ g->add_node('u')->add_node('v')->add_node('x')->add_node('y');
+ g->add_node('w')->add_node('z');
+ g->add_edge('u', 'v');
+ g->add_edge('u', 'x');
+ g->add_edge('x', 'v');
+ g->add_edge('y', 'x');
+ g->add_edge('v', 'y');
+ g->add_edge('w', 'y');
+ g->add_edge('w', 'z');
+ g->add_edge('z', 'z');
+
+ g->print();
+ g->dfs();
+
+ delete g;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/graph.cc b/1_anno/Programmazione_2/data_structures/graph.cc
new file mode 100644
index 0000000..12837be
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/graph.cc
@@ -0,0 +1,164 @@
+#include<iostream>
+#include<vector>
+
+using namespace std;
+
+template<class H>
+class node {
+public:
+ explicit node(H key, node<H>* next) : _key{key}, _next(next) {}
+ const H& key() const { return _key; }
+ H& key() { return _key; }
+ const node<H>*& next() const { return _next; }
+ node<H>*& next() { return _next; }
+private:
+ H _key;
+ node<H>* _next;
+};
+
+template<class H>
+class list {
+public:
+ list() : _head{nullptr} {}
+ ~list() {
+ while(_head) {
+ auto tmp = _head;
+ _head = _head->next();
+ delete tmp;
+ }
+ }
+ list<H>* push(H val) {
+ auto iter = _head;
+ while(iter && iter->next())
+ iter = iter->next();
+
+ if(!iter)
+ _head = new node<H>{val, nullptr};
+ else
+ iter->next() = new node<H>{val, nullptr};
+
+ return this;
+ }
+ list<H>* pop(H val) {
+ auto elem = search(val);
+ if(!elem)
+ return this;
+
+ auto iter = _head;
+ // This is the case when head is the element we want to pop
+ if(iter == elem) {
+ delete _head;
+ _head = nullptr;
+ return this;
+ }
+
+ while(iter && iter->next() != elem)
+ iter = iter->next();
+
+ auto tmp = iter->next();
+ if(iter->next()->next()) {
+ iter->next() = iter->next()->next();
+ } else { // the element we want to pop is the tail
+ iter->next() = nullptr;
+ }
+ delete tmp;
+
+ return this;
+ }
+ void print() {
+ auto iter = _head;
+ while(iter) {
+ cout << iter->key() << ' ';
+ iter = iter->next();
+ }
+ }
+ vector<H> as_vector() {
+ vector<H> v;
+ auto iter = _head;
+ while(iter) {
+ v.push_back(iter->key());
+ iter = iter->next();
+ }
+ return v;
+ }
+ node<H>* search(H val) {
+ auto iter = _head;
+ while(iter && iter->key() != val) {
+ iter = iter->next();
+ }
+
+ return iter;
+ }
+private:
+ node<H>* _head;
+};
+
+template<class H>
+class graph {
+public:
+
+private:
+ int _len, _nodes, _edges;
+ H **_k;
+ list<int> **_adj;
+ int _index(H val) {
+ for(int i = 0; i < _nodes; ++i)
+ if(*_k[i] == val) return i;
+
+ return -1;
+ }
+public:
+ graph(int len) : _len{len}, _nodes{0}, _edges{0} {
+ _k = new H*[len];
+ _adj = new list<int>*[_len];
+ for(int i = 0; i < _len; ++i) {
+ _k[i] = nullptr;
+ _adj[i] = new list<int>{};
+ }
+ }
+
+ graph<H>* add_node(H k) {
+ if(_nodes == _len) return this;
+ if(_index(k) >= 0) return this; // node is already there
+
+ _k[_nodes++] = new H(k);
+
+ return this;
+ }
+
+ graph<H>* add_edge(H x, H y) {
+ int i = _index(x);
+ int j = _index(y);
+ if(i < 0 || j < 0) return this;
+
+ if(!_adj[i]->search(j)) {
+ _adj[i]->push(j);
+ _edges++;
+ }
+
+ return this;
+ }
+
+ void print() {
+ for(int i = 0; i < _nodes; ++i) {
+ cout << "(" << i << ", " << *_k[i] << "): ";
+ for(auto const& j : _adj[i]->as_vector())
+ cout << "(" << j << ", " << *_k[j] << "), ";
+ cout << '\n';
+ }
+ }
+};
+
+
+int main() {
+ graph<string>* g = new graph<string>(5);
+ g->add_node("hello")->add_node("greg")->add_node("yes");
+ g->add_node("nop")->add_node("ok");
+ g->add_edge("hello", "ok");
+ g->add_edge("ok", "yes")->add_edge("yes", "ok")->add_edge("yes", "yes");
+ g->add_edge("yes", "nop");
+ g->print();
+
+ delete g;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/graph_stl.cc b/1_anno/Programmazione_2/data_structures/graph_stl.cc
new file mode 100644
index 0000000..5381747
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/graph_stl.cc
@@ -0,0 +1,221 @@
+#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;
+}
diff --git a/1_anno/Programmazione_2/data_structures/list.cc b/1_anno/Programmazione_2/data_structures/list.cc
new file mode 100644
index 0000000..8ddcbf9
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/list.cc
@@ -0,0 +1,164 @@
+#include<iostream>
+
+using namespace std;
+
+template<typename T>
+struct node {
+ T value;
+ node* next;
+};
+
+
+template<typename T>
+class list {
+public:
+ list() : _head{nullptr} {}
+
+ ~list() {
+ while(_head) {
+ node<T>* tmp = _head->next;
+ delete tmp;
+ _head = tmp;
+ }
+ }
+
+ list* push_front(T val) {
+ _head = new node<T>{val, _head};
+
+ return this;
+ }
+
+ list* push_back(T val) {
+ if(!_head) return this->push_front(val);
+
+ node<T>* iter = _head;
+ while(iter->next) {
+ iter = iter->next;
+ }
+ iter->next = new node<T>{val, nullptr};
+
+ return this;
+ }
+
+ list* push_after_value(T val, T newval) {
+ node<T>* iter = _search(val);
+ if(iter)
+ iter->next = new node<T>{newval, iter->next};
+
+ return this;
+ }
+
+ list* push_before_value(T val, T newval) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ node<T>* iter = _head;
+
+ if(iter->value == val)
+ return this->push_front(newval);
+
+ while(iter->next != elem)
+ iter = iter->next;
+
+ iter->next = new node<T>{newval, iter->next};
+
+ return this;
+ }
+
+ list* pop(int val) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ node<T>* iter = _head;
+ if(iter == elem) return this->pop_front();
+
+ while(iter->next != elem)
+ iter = iter->next;
+
+ node<T>* temp = iter->next;
+ iter->next = iter->next->next;
+ delete temp;
+
+ return this;
+ }
+
+ list* pop_front() {
+ if(!_head)
+ return this;
+
+ node<T>* elem = _head;
+ _head = _head->next;
+ delete elem;
+
+ return this;
+ }
+
+ list* pop_back() {
+ if(!_head)
+ return this;
+
+ node<T>* iter = _head;
+
+ while(iter->next && iter->next->next) {
+ iter = iter->next;
+ }
+
+ if(!iter->next) {
+ delete iter;
+ _head = nullptr;
+ } else if(iter->next->next) {
+ delete iter->next->next;
+ } else {
+ delete iter->next;
+ }
+
+ iter->next = nullptr;
+
+ return this;
+ }
+
+ void print() {
+ node<T>* iter = _head;
+ while(iter) {
+ cout << iter->value << ' ';
+ iter = iter->next;
+ }
+ }
+private:
+ node<T>* _search(T value) {
+ node<T>* iter = _head;
+ while(iter && iter->value != value)
+ iter = iter->next;
+
+ return iter;
+ }
+
+ node<T>* _head;
+};
+
+int main() {
+ list<int>* l = new list<int>{};
+ l->push_front(2)->push_front(1);
+ l->print(); cout << endl;
+ l->push_back(5);
+ l->print(); cout << endl;
+ l->push_back(10)->push_back(15);
+ l->print(); cout << endl;
+ l->push_after_value(5, 6);
+ l->print(); cout << endl;
+ l->push_before_value(5, 4);
+ l->print(); cout << endl;
+ l->push_before_value(4, 3);
+ l->print(); cout << endl;
+ l->pop_back();
+ l->print(); cout << endl;
+ l->pop_front();
+ l->print(); cout << endl;
+ l->push_front(1);
+ l->print(); cout << endl;
+ l->pop(1);
+ l->print(); cout << endl;
+
+ delete l;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/list_double.cc b/1_anno/Programmazione_2/data_structures/list_double.cc
new file mode 100644
index 0000000..fa0af26
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/list_double.cc
@@ -0,0 +1,182 @@
+#include<iostream>
+
+using namespace std;
+
+template<typename T>
+struct node {
+ T value;
+ node* prev;
+ node* next;
+};
+
+
+template<typename T>
+class list {
+public:
+ list() : _head{nullptr} {}
+
+ ~list() {
+ while(_head != nullptr) {
+ node<T>* tmp = _head->next;
+ delete tmp;
+ _head = tmp;
+ }
+ }
+
+ list* push_front(T val) {
+ if(!_head) {
+ _head = new node<T>{val, nullptr, nullptr};
+ } else {
+ _head = new node<T>{val, nullptr, _head};
+ _head->next->prev = _head;
+ }
+
+ return this;
+ }
+
+ list* push_back(T val) {
+ if(!_head) return this->push_front(val);
+
+ node<T>* iter = _head;
+ while(iter->next) {
+ iter = iter->next;
+ }
+ iter->next = new node<T>{val, iter, nullptr};
+
+ return this;
+ }
+
+ list* push_after_value(T val, T newval) {
+ node<T>* elem = _search(val);
+ if(elem) {
+ node<T>* nod = new node<T>{newval, elem, elem->next};
+ elem->next = nod;
+ nod->next->prev = nod;
+ }
+
+ return this;
+ }
+
+ list* push_before_value(T val, T newval) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ node<T>* iter = _head;
+
+ if(iter->value == val)
+ return this->push_front(newval);
+
+ while(iter->next != elem)
+ iter = iter->next;
+
+ node<T>* nod = new node<T>{newval, iter, iter->next};
+ iter->next = nod;
+ nod->next->prev = nod;
+
+ return this;
+ }
+
+ list* pop(int val) {
+ node<T>* elem = _search(val);
+ if(!elem) return this;
+
+ if(elem == _head) return this->pop_front();
+
+ node<T>* iter = elem->prev;
+ node<T>* temp = iter->next;
+ iter->next = iter->next->next;
+ iter->next->prev = iter;
+ delete temp;
+
+ return this;
+ }
+
+ list* pop_front() {
+ if(!_head)
+ return this;
+
+ node<T>* elem = _head;
+ _head = _head->next;
+ _head->prev = nullptr;
+ delete elem;
+
+ return this;
+ }
+
+ list* pop_back() {
+ if(!_head)
+ return this;
+
+ node<T>* iter = _last()->prev;
+
+ if(iter->next == nullptr) {
+ delete iter;
+ _head = nullptr;
+ } else if(iter->next->next) {
+ delete iter->next->next;
+ } else {
+ delete iter->next;
+ }
+
+ iter->next = nullptr;
+
+ return this;
+ }
+
+ void print() {
+ node<T>* iter = _head;
+ while(iter) {
+ cout << iter->value << ' ';
+ cout << "[[ " << (iter->prev!=nullptr ? iter->prev->value : -1) << ", ";
+ cout << (iter->next!=nullptr ? iter->next->value : -1) << " ]], ";
+ iter = iter->next;
+ }
+ }
+private:
+ node<T>* _last() {
+ node<T>* iter = _head;
+ while(iter->next) {
+ iter = iter->next;
+ }
+
+ return iter;
+ }
+
+ node<T>* _search(T value) {
+ node<T>* iter = _head;
+ while(iter && iter->value != value)
+ iter = iter->next;
+
+ return iter;
+ }
+
+ node<T>* _head;
+};
+
+int main() {
+ list<int>* l = new list<int>{};
+ l->push_front(2)->push_front(1);
+ l->print(); cout << endl;
+ l->push_back(5);
+ l->print(); cout << endl;
+ l->push_back(10)->push_back(15);
+ l->print(); cout << endl;
+ l->push_after_value(5, 6);
+ l->print(); cout << endl;
+ l->push_after_value(5, 7);
+ l->print(); cout << endl;
+ l->push_before_value(5, 4);
+ l->print(); cout << endl;
+ l->push_before_value(5, 3);
+ l->print(); cout << endl;
+ l->pop_back();
+ l->print(); cout << endl;
+ l->pop_front();
+ l->print(); cout << endl;
+ l->pop(2);
+ l->print(); cout << endl;
+
+ delete l;
+
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/matrix-graph.cc b/1_anno/Programmazione_2/data_structures/matrix-graph.cc
new file mode 100644
index 0000000..a644ec1
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/matrix-graph.cc
@@ -0,0 +1,81 @@
+#include<iostream>
+#include<list>
+
+using namespace std;
+
+template<class H>
+class matrix_graph {
+public:
+ ~matrix_graph() {
+ delete[] _m;
+ delete[] _k;
+ }
+ matrix_graph(int len) : _len{len}, _nodes{0}, _edges{0} {
+ _m = new int*[len];
+ _k = new H*[len];
+ for(int i = 0; i < len; ++i) {
+ _m[i] = new int[len];
+ _k[i] = nullptr;
+ for(int j = 0; j < len; ++j)
+ _m[i][j] = 0;
+ }
+ }
+
+ matrix_graph<H>* add_node(H k) {
+ if(_len == _nodes) return this; // no more space for new nodes
+ if(_index(k) > -1) return this; // nodes already exists
+
+ _k[_nodes++] = new H(k);
+
+ return this;
+ }
+
+ matrix_graph<H>* add_edge(H x, H y) {
+ int i = _index(x);
+ int j = _index(y);
+ if(i < 0 || j < 0) return this;
+ if(!_m[i][j]) {
+ _m[i][j] = 1;
+ _edges++;
+ }
+ return this;
+ }
+ void print() {
+ for(int i = 0; i < _len; ++i) {
+ cout << i << ' ' << *_k[i] << ": ";
+ for(int j = 0; j < _len; ++j) {
+ if(_m[i][j])
+ cout << *_k[j] << ' ';
+ }
+ cout << '\n';
+ }
+ cout << endl;
+ for(int i = 0; i < _len; ++i) {
+ for(int j = 0; j < _len; ++j) {
+ cout << _m[i][j] << ' ';
+ }
+ cout << '\n';
+ }
+ }
+private:
+ int _len, _nodes, _edges;
+ int** _m;
+ H** _k;
+ int _index(H x) {
+ for(int i = 0; i < _nodes; ++i)
+ if(*_k[i] == x) return i;
+ return -1;
+ }
+};
+
+int main() {
+ matrix_graph<string>* g = new matrix_graph<string>(5);
+ g->add_node("hello")->add_node("greg")->add_node("yes");
+ g->add_node("nop")->add_node("ok");
+ g->add_edge("hello", "ok");
+ g->add_edge("ok", "yes")->add_edge("yes", "ok")->add_edge("yes", "yes");
+ g->add_edge("yes", "nop");
+ g->print();
+ delete g;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/queue.cc b/1_anno/Programmazione_2/data_structures/queue.cc
new file mode 100644
index 0000000..8398459
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/queue.cc
@@ -0,0 +1,72 @@
+#include<iostream>
+
+using namespace std;
+
+template<typename T>
+struct node {
+ T value;
+ node<T>* next;
+};
+
+template<class T>
+class queue {
+public:
+ queue() : _head{nullptr} {}
+
+ ~queue() {
+ auto iter = _head;
+ while(iter) {
+ delete iter;
+ iter = iter->next;
+ }
+ }
+
+ queue<T>* enqueue(T val) {
+
+ if(!_head) {
+ _head = new node<T>{val, nullptr};
+ _tail = _head;
+ } else {
+ _tail->next = new node<T>{val, nullptr};
+ _tail = _tail->next;
+ }
+
+ return this;
+ }
+
+ node<T>* dequeue() {
+ if(!_head) return nullptr;
+ auto iter = _head;
+ delete _head;
+ _head = iter->next;
+ return iter;
+ }
+
+ void print() {
+ auto iter = _head;
+ while(iter) {
+ cout << iter->value << ' ';
+ iter = iter->next;
+ }
+ cout << endl;
+ }
+private:
+ node<T>* _head;
+ node<T>* _tail;
+};
+
+int main() {
+ queue<int>* q = new queue<int>();
+
+ q->dequeue();
+ q->enqueue(4)->enqueue(2)->enqueue(8);
+ q->print();
+ auto e = q->dequeue();
+ if(e)
+ cout << e->value << endl;
+ q->enqueue(1);
+ q->print();
+
+ delete q;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/queue_w_array.cc b/1_anno/Programmazione_2/data_structures/queue_w_array.cc
new file mode 100644
index 0000000..fb92d68
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/queue_w_array.cc
@@ -0,0 +1,66 @@
+#include<iostream>
+
+using namespace std;
+
+template<class H>
+class queue {
+public:
+ queue(int n) : _size{n}, _counter{0}, _head{0}, _tail{0} {
+ _arr = new H[n];
+ }
+ ~queue() {
+ delete _arr;
+ }
+ bool is_empty() {
+ return _counter == 0;
+ }
+ bool is_full() {
+ return _counter == _size;
+ }
+
+ queue<H>* enqueue(H x) {
+ if(!is_full()) {
+ _arr[_tail] = x;
+ if(_tail == _size-1)
+ _tail = 0;
+ else
+ ++_tail;
+ _counter++;
+ }
+
+ return this;
+ }
+ H dequeue() {
+ if(is_empty()) return -1;
+ H x = _arr[_head];
+
+ if(_head == _size-1)
+ _head = 0;
+ else
+ ++_head;
+
+ _counter--;
+ return x;
+ }
+private:
+ H* _arr;
+ int _size;
+ short _counter;
+ short _head;
+ short _tail;
+};
+
+int main() {
+ queue<int>* q = new queue<int>{4};
+ q->enqueue(5)->enqueue(13)->enqueue(3);
+ cout << q->dequeue() << '\n';
+ q->enqueue(4)->enqueue(6)->enqueue(7);
+ q->dequeue();
+ q->enqueue(7);
+
+ for(int i = 0; i < 6; ++i) {
+ cout << q->dequeue() << ' ';
+ }
+ delete q;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/stack.cc b/1_anno/Programmazione_2/data_structures/stack.cc
new file mode 100644
index 0000000..ffff780
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/stack.cc
@@ -0,0 +1,70 @@
+#include<iostream>
+
+using namespace std;
+
+template<typename T>
+struct node {
+ T value;
+ node<T>* next;
+};
+
+template<class T>
+class stack {
+public:
+ stack() : _head{nullptr} {}
+
+ ~stack() {
+ auto iter = _head;
+ while(iter) {
+ delete iter;
+ iter = iter->next;
+ }
+ }
+
+ stack<T>* push(T val) {
+
+ if(!_head) {
+ _head = new node<T>{val, nullptr};
+ } else {
+ _head = new node<T>{val, _head};
+ }
+
+ return this;
+ }
+
+ node<T>* pop() {
+ if(!_head) return nullptr;
+ node<T>* elem = _head;
+ delete _head;
+ _head = elem->next;
+
+ return elem;
+ }
+
+ void print() {
+ auto iter = _head;
+ while(iter) {
+ cout << iter->value << ' ';
+ iter = iter->next;
+ }
+ cout << endl;
+ }
+private:
+ node<T>* _head;
+};
+
+int main() {
+ stack<int>* s = new stack<int>();
+
+ s->pop();
+ s->push(4)->push(2)->push(8);
+ s->print();
+ auto e = s->pop();
+ if(e)
+ cout << e->value << endl;
+ s->push(1);
+ s->print();
+
+ delete s;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/stack_w_array.cc b/1_anno/Programmazione_2/data_structures/stack_w_array.cc
new file mode 100644
index 0000000..c20db90
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/stack_w_array.cc
@@ -0,0 +1,50 @@
+#include<iostream>
+
+using namespace std;
+
+template<class H>
+class stack {
+public:
+ stack(int n) : _size{n}, _top{-1} {
+ _arr = new H[n];
+ }
+ ~stack() {
+ delete _arr;
+ }
+ bool is_empty() {
+ return _top == -1;
+ }
+ bool is_full() {
+ return _top == _size-1;
+ }
+ stack<H>* push(H x) {
+ if(!is_full()) {
+ _arr[++_top] = x;
+ }
+ return this;
+ }
+ H pop() {
+ if(is_empty())
+ return -1;
+ _top--;
+ return _arr[_top+1];
+ }
+private:
+ int _size;
+ H* _arr;
+ short _top;
+};
+
+int main() {
+ stack<int>* s = new stack<int>{7};
+
+ s->push(15)->push(6)->push(2)->push(9)->push(17)->push(3);
+ cout << s->pop() << '\n';
+ s->push(18)->push(19)->push(12);
+
+ for(int i = 0; i < 7; ++i)
+ cout << s->pop() << ' ';
+
+ delete s;
+ return 0;
+}
diff --git a/1_anno/Programmazione_2/data_structures/top-sort.cc b/1_anno/Programmazione_2/data_structures/top-sort.cc
new file mode 100644
index 0000000..7441ee9
--- /dev/null
+++ b/1_anno/Programmazione_2/data_structures/top-sort.cc
@@ -0,0 +1,212 @@
+
+#include<iostream>
+#include<vector>
+#include<queue>
+#define W -1
+#define G 0
+#define B 1
+
+using namespace std;
+
+template<class H>
+class node {
+public:
+ explicit node(H key, node<H>* next) : _key{key}, _next(next) {}
+ const H& key() const { return _key; }
+ H& key() { return _key; }
+ const node<H>*& next() const { return _next; }
+ node<H>*& next() { return _next; }
+private:
+ H _key;
+ node<H>* _next;
+};
+
+template<class H>
+class list {
+public:
+ list() : _head{nullptr} {}
+ ~list() {
+ while(_head) {
+ auto tmp = _head;
+ _head = _head->next();
+ delete tmp;
+ }
+ }
+ list<H>* push(H val) {
+ auto iter = _head;
+ while(iter && iter->next())
+ iter = iter->next();
+
+ if(!iter)
+ _head = new node<H>{val, nullptr};
+ else
+ iter->next() = new node<H>{val, nullptr};
+
+ return this;
+ }
+ void print() {
+ auto iter = _head;
+ while(iter) {
+ cout << iter->key() << ' ';
+ iter = iter->next();
+ }
+ }
+ vector<H> as_vector() {
+ vector<H> v;
+ auto iter = _head;
+ while(iter) {
+ v.push_back(iter->key());
+ iter = iter->next();
+ }
+ return v;
+ }
+ node<H>* search(H val) {
+ auto iter = _head;
+ while(iter && iter->key() != val) {
+ iter = iter->next();
+ }
+
+ return iter;
+ }
+private:
+ node<H>* _head;
+};
+
+template<class H>
+class graph {
+private:
+ int _len, _nodes, _edges;
+ int* _parents;
+ int* _radixes;
+ int* _distances;
+ int* _finishes;
+ int* _colors;
+ int _time;
+ int _current;
+ H** _k; // it works like a dictionary, it saves the keys
+ list<int>** _adj;
+ int _index(H val) {
+ for(int i = 0; i < _nodes; ++i)
+ if(*_k[i] == val) return i;
+
+ return -1;
+ }
+ bool _dfsvisit(int u) {
+ bool cycle = false;
+ _colors[u] = G;
+ _distances[u] = _time++;
+ _radixes[u] = _current;
+ for(auto const& v : _adj[u]->as_vector()) {
+ if(_colors[v] == W) {
+ _parents[v] = u;
+ _dfsvisit(v);
+ } else if(_colors[v] == G) {
+ cycle = true;
+ }
+ }
+ _colors[u] = B;
+ _finishes[u] = _time++;
+ return cycle;
+ }
+public:
+ graph(int len) : _len{len}, _nodes{0}, _edges{0} {
+ _k = new H*[len];
+ _adj = new list<int>*[_len];
+ _parents = new int[_len];
+ _radixes = new int[_len];
+ _distances = new int[_len];
+ _finishes = new int[_len];
+ _colors = new int[_len];
+ for(int i = 0; i < _len; ++i) {
+ _k[i] = nullptr;
+ _adj[i] = new list<int>{};
+ }
+ }
+
+ graph<H>* add_node(H k) {
+ if(_nodes == _len) return this;
+ if(_index(k) >= 0) return this; // node is already there
+
+ _k[_nodes++] = new H(k);
+
+ return this;
+ }
+
+
+ bool dfs() {
+ bool cycle = 0;
+ _time = 0;
+ for(int i = 0; i < _nodes; ++i) {
+ _colors[i] = W;
+ _parents[i] = -1;
+ }
+
+ for(int i = 0; i < _nodes; ++i) {
+ if(_colors[i] == W) {
+ _current = i;
+ cycle |= _dfsvisit(i);
+ }
+ }
+ for(int i = 0; i < _nodes; ++i) {
+ cout << *_k[i] << "(" << _distances[i]+1 << ',' << _finishes[i]+1 << ")" << endl;
+ }
+ return cycle;
+ }
+
+ void top_sort() {
+ bool cycle = dfs();
+ if(cycle) {
+ cerr << "Grafo ciclico\n";
+ return;
+ }
+ vector<int> s(_finishes, _finishes+_nodes);
+ sort(begin(s), end(s));
+ for(auto const& i : s) {
+ cout << "(" << i << ", " << _finishes[i] << ") ";
+ }
+ }
+
+ graph<H>* add_edge(H x, H y) {
+ int i = _index(x);
+ int j = _index(y);
+ if(i < 0 || j < 0) return this;
+
+ if(!_adj[i]->search(j)) {
+ _adj[i]->push(j);
+ _edges++;
+ }
+
+ return this;
+ }
+
+ void print() {
+ for(int i = 0; i < _nodes; ++i) {
+ cout << "(" << i << ", " << *_k[i] << "): ";
+ for(auto const& j : _adj[i]->as_vector())
+ cout << "(" << j << ", " << *_k[j] << "), ";
+ cout << '\n';
+ }
+ }
+};
+
+
+int main() {
+ graph<char>* g = new graph<char>(6);
+ g->add_node('u')->add_node('v')->add_node('x')->add_node('y');
+ g->add_node('w')->add_node('z');
+ g->add_edge('u', 'v');
+ g->add_edge('u', 'x');
+ g->add_edge('x', 'v');
+ g->add_edge('y', 'x');
+ g->add_edge('v', 'y');
+ g->add_edge('w', 'y');
+ g->add_edge('w', 'z');
+ g->add_edge('z', 'z');
+
+ g->print();
+ g->dfs();
+ g->top_sort();
+
+ delete g;
+ return 0;
+}