leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
Log | Files | Refs | README | LICENSE

0142.cpp (565B)

      1 class Solution {
      2   public:
      3     ListNode *detectCycle(ListNode *head) {
      4         if (!head) return nullptr;
      5 
      6         ListNode *slow, *fast;
      7         fast = slow = head;
      8         while (fast->next && fast->next->next) {
      9             fast = fast->next->next;
     10             slow = slow->next;
     11             if (fast == slow) {
     12                 fast = head;
     13                 while (fast != slow) {
     14                     fast = fast->next;
     15                     slow = slow->next;
     16                 }
     17                 return slow;
     18             }
     19         }
     20         return nullptr;
     21     }
     22 };