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authorSanto Cariotti <santo@dcariotti.me>2021-02-06 19:56:36 +0100
committerSanto Cariotti <santo@dcariotti.me>2021-02-06 19:56:36 +0100
commitd2edbc38cac8da52f58c5cd3da6c0c625fa05736 (patch)
treea51e9a4e56fc9d4c7c9e37576dceedca3a0c72b4 /Year_1/Programming_2/data_structures/circle_list.cc
parent98f34040820dc3a964b7be59a698323e8cc6c8a3 (diff)
conf: rename
Diffstat (limited to 'Year_1/Programming_2/data_structures/circle_list.cc')
-rw-r--r--Year_1/Programming_2/data_structures/circle_list.cc189
1 files changed, 189 insertions, 0 deletions
diff --git a/Year_1/Programming_2/data_structures/circle_list.cc b/Year_1/Programming_2/data_structures/circle_list.cc
new file mode 100644
index 0000000..2143ac1
--- /dev/null
+++ b/Year_1/Programming_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;
+}