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Diffstat (limited to 'I_anno/Programmazione_2/data_structures/list_double.cc')
-rw-r--r--I_anno/Programmazione_2/data_structures/list_double.cc76
1 files changed, 29 insertions, 47 deletions
diff --git a/I_anno/Programmazione_2/data_structures/list_double.cc b/I_anno/Programmazione_2/data_structures/list_double.cc
index 9dc11b7..79cd8c3 100644
--- a/I_anno/Programmazione_2/data_structures/list_double.cc
+++ b/I_anno/Programmazione_2/data_structures/list_double.cc
@@ -23,22 +23,6 @@ public:
}
}
- node<T>* search(T val) {
- if(_head == nullptr) return nullptr;
-
- 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;
- }
-
list* push_front(T val) {
if(_head == nullptr) {
_head = new node<T>{val, nullptr, nullptr};
@@ -51,50 +35,40 @@ public:
}
list* push_back(T val) {
+ if(!_head) return this->push_front(val);
+
node<T>* iter = _head;
- if(_head == nullptr) {
- _head = new node<T>{val, nullptr, nullptr};
- } else {
- while(iter->next != nullptr) {
- iter = iter->next;
- }
- iter->next = new node<T>{val, iter, nullptr};
+ while(iter->next) {
+ iter = iter->next;
}
+ iter->next = new node<T>{val, iter, nullptr};
return this;
}
list* push_after_value(T val, T newval) {
- if(!search(val)) return this;
-
- node<T>* iter = _head;
- while(iter && iter->value != val)
- iter = iter->next;
-
- if(iter == nullptr)
- return this->push_front(newval);
-
- node<T>* nod = new node<T>{newval, iter, iter->next};
- iter->next = nod;
- nod->next->prev = nod;
+ 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) {
- if(!search(val)) return this;
+ node<T>* elem = _search(val);
+ if(!elem) return this;
node<T>* iter = _head;
if(iter->value == val)
return this->push_front(newval);
- while(iter && iter->next && iter->next->value != val)
+ while(iter->next != elem)
iter = iter->next;
- if(iter == nullptr)
- return this->push_front(newval);
-
node<T>* nod = new node<T>{newval, iter, iter->next};
iter->next = nod;
nod->next->prev = nod;
@@ -103,15 +77,13 @@ public:
}
list* pop(int val) {
- if(_head == nullptr)
- return this;
- else if(_head->value == val)
- return pop_front();
-
- if(!search(val)) return this;
+ node<T>* elem = _search(val);
+ if(!elem) return this;
node<T>* iter = _head;
- while(iter && iter->next && iter->next->value != val)
+ if(iter == elem) return this->pop_front();
+
+ while(iter->next != elem)
iter = iter->next;
node<T>* temp = iter->next;
@@ -168,6 +140,14 @@ public:
}
}
private:
+ node<T>* _search(T value) {
+ node<T>* iter = _head;
+ while(iter && iter->value != value)
+ iter = iter->next;
+
+ return iter;
+ }
+
node<T>* _head;
};
@@ -194,5 +174,7 @@ int main() {
l->pop(2);
l->print(); cout << endl;
+ delete l;
+
return 0;
}