| 6 | DFS | [Slides](slides/S6_DFS&BFS.pdf) <br /> [Leetcode problem: Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) <br /> | |

| 7 | Backtracking | [Slides](slides/S7_Backtracking.pdf) <br /> [Leetcode problem: Subsets](https://leetcode.com/problems/subsets/) <br /> | |

| 8 | Bonus Pattern I | [Slides](slides/S8_BonusPatterns#1.pdf) <br /> [Leetcode problem: Validate BST](https://leetcode.com/problems/validate-binary-search-tree/) <br /> [Leetcode problem: Binary Tree Right Side View](https://leetcode.com/problems/binary-tree-right-side-view/) <br /> [Leetcode problem: Linked List Cycle](https://leetcode.com/problems/linked-list-cycle/) | |

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