#include "s0142_linked_list_cycle.hpp"

#include <gtest/gtest.h>

TEST(Problem142, Case1) {
  ListNode node1 = ListNode(3);
  ListNode node2 = ListNode(2);
  ListNode node3 = ListNode(0);
  ListNode node4 = ListNode(-4);
  node1.next = &node2;
  node2.next = &node3;
  node3.next = &node4;
  node4.next = &node2;
  S0142 solution;
  EXPECT_EQ(solution.detectCycle(&node1), &node2);
}

TEST(Problem142, Case2) {
  ListNode node1 = ListNode(3);
  ListNode node2 = ListNode(2);
  ListNode node3 = ListNode(0);
  ListNode node4 = ListNode(-4);
  node1.next = &node2;
  node2.next = &node3;
  node3.next = &node4;
  node4.next = &node1;
  S0142 solution;
  EXPECT_EQ(solution.detectCycle(&node1), &node1);
}

TEST(Problem142, Case3) {
  ListNode node1 = ListNode(3);
  ListNode node2 = ListNode(2);
  ListNode node3 = ListNode(0);
  ListNode node4 = ListNode(-4);
  node1.next = &node2;
  node2.next = &node3;
  node3.next = &node4;
  S0142 solution;
  EXPECT_EQ(solution.detectCycle(&node1), nullptr);
}

TEST(Problem142, Case4) {
  ListNode node1 = ListNode(1);
  ListNode node2 = ListNode(2);
  node1.next = &node2;
  node2.next = &node1;
  S0142 solution;
  EXPECT_EQ(solution.detectCycle(&node1), &node1);
}

TEST(Problem142, Case5) {
  ListNode node1 = ListNode(1);
  node1.next = &node1;
  S0142 solution;
  EXPECT_EQ(solution.detectCycle(&node1), &node1);
}