From f3f1bd47f8af2c5c445d2201792d82dd02b24c9b Mon Sep 17 00:00:00 2001 From: Santo Cariotti Date: Sat, 9 May 2020 11:59:05 +0200 Subject: fix: search function --- .../Programmazione_2/data_structures/circle_list.cc | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'I_anno/Programmazione_2/data_structures/circle_list.cc') diff --git a/I_anno/Programmazione_2/data_structures/circle_list.cc b/I_anno/Programmazione_2/data_structures/circle_list.cc index ee32a8c..b6be463 100644 --- a/I_anno/Programmazione_2/data_structures/circle_list.cc +++ b/I_anno/Programmazione_2/data_structures/circle_list.cc @@ -31,6 +31,22 @@ public: return iter; } + node* search(T val) { + if(_head == nullptr) return nullptr; + + node* 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) { auto elem = last_element(); _head = new node{val, _head}; @@ -56,6 +72,8 @@ public: } list* push_after_value(T val, T newval) { + if(!search(val)) return this; + node* iter = _head; while(iter && iter->value != val) iter = iter->next; @@ -69,6 +87,8 @@ public: } list* push_before_value(T val, T newval) { + if(!search(val)) return this; + node* iter = _head; if(iter->value == val) @@ -140,6 +160,7 @@ private: int main() { list* l = new list{}; + l->push_before_value(4, 1); l->push_back(4); l->push_back(1); l->push_back(0); -- cgit v1.2.3-18-g5258