#ifndef S0142_LINKED_LIST_CYCLE_HPP
#define S0142_LINKED_LIST_CYCLE_HPP

#include <unordered_map>

struct ListNode {
  int val;
  ListNode* next;
  ListNode(int x) : val(x), next(nullptr) {}
};

struct IterResult {
  ListNode *node;
  bool meet;
};

class S0142 {
 public:
  std::unordered_map<ListNode *, int> footprint;
  IterResult iter(ListNode *fast, ListNode* slow, bool startUp);
  ListNode *detectCycle(ListNode *head);
};

#endif