leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
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2074.cpp (798B)

      1 class Solution {
      2   public:
      3     ListNode *reverseEvenLengthGroups(ListNode *head) {
      4         ListNode *prev = head, *crnt = head->next;
      5 
      6         for (int lvl = 2; crnt; lvl++) {
      7             ListNode *bg = prev;
      8 
      9             int size = 0;
     10             while (crnt && size < lvl) {
     11                 prev = crnt;
     12                 crnt = crnt->next;
     13                 size++;
     14             }
     15 
     16             if (size % 2) continue;
     17 
     18             crnt = bg->next;
     19             ListNode *last = crnt, *first = crnt, *tmp;
     20             while (size--) {
     21                 tmp = crnt;
     22                 crnt = crnt->next;
     23                 tmp->next = last;
     24                 last = tmp;
     25             }
     26             bg->next = last;
     27             first->next = crnt;
     28             prev = first;
     29         }
     30 
     31         return head;
     32     }
     33 };