leetcode

Solution to some Leetcode problems written in C++

git clone git://git.dimitrijedobrota.com/leetcode.git

1472.cpp (882B)

0 class BrowserHistory { 1 struct Node { 2 Node *next, *prev; 3 string val; 4 Node(string val = "#", Node *prev = nullptr, Node *next = nullptr) 5 : val(val), prev(prev), next(next) {} 6 }; 7 Node *head = nullptr, *tail = nullptr, *crnt = nullptr; 8 9 public: 10 BrowserHistory(string homepage) { crnt = head = tail = new Node(homepage); } 11 12 void visit(string url) { 13 for (Node *t = tail->next; t;) { 14 Node *tmp = t; 15 t = t->next; 16 delete tmp; 17 } 18 crnt = tail = tail->next = new Node(url, tail, nullptr); 19 } 20 21 string back(int steps) { 22 while (steps-- && crnt->prev) 23 tail = crnt = crnt->prev; 24 return crnt->val; 25 } 26 27 string forward(int steps) { 28 while (steps-- && crnt->next) 29 tail = crnt = crnt->next; 30 return crnt->val; 31 } 32 };